I suprisingly noticed that there are (up to now) no character/class builds shared on steam, so I decided to refine and share my personal concept with the community:
Using a dexterity build we are able to gain high dexterity saves, high armor class (AC), high hit and damage modifiers, as well as being able to disarm most traps and open most locks. This build relies on auto attacks, combined with very fast attack speed it dishes out loads of critical hits and damage. This build is very potent, being able to solo any dungeon crawl on level 20 with hardest settings.

Let's get down to business!

Race:
I would make the choice up to your personal preference or role playing purposes but I strongly recommend picking one of the mentioned races below (because of their dexterity bonuses).
The attribute distribution changes depending on your chosen race.

Recommended Race:
Strongheart Halfling:
+2 Dexterity, +1 Constitution, 50% poison resistance

Optional Races:
Wood Elf:
+2 Dexterity, +1 Wisdom, 10% Movement Speed Bonus, Sleep Immunity, Racial Bonus to Search

Drow (Elf):
+2 Dexterity, +1 Charisma, Faerie Fire & Darkness, Sleep Immunity, Racial Bonus to Search
(If you want to be a Drow: please check out the section "Community Pack Two Patch" right now)

Class:
Fighter

Background:
Charlatan +1 CHA, +2 to Wisdom and Charisma saves
Outlander: +1 Constitution, -2 physical damage taken (pick this for Drow only!)


Distribute your points like this during character creation:

Strongheart Halfling:
Start with 12 Strength, 16 Dexterity, 16 Constitution, 8 Intelligence, 14 Wisdom, 9 Charisma

Wood Elf:
Start with 12 strength, 16 Dexterity, 15 Constitution, 8 Intelligence, 15 Wisdom, 9 Charisma

Drow:
Start with 12 strength, 17 Dexterity, 16 Constitution, 8 Intelligence, 13 Wisdom, 9 Charisma

Example (Strongheart Halfling):

As you level up:
First maximize Dexterity (20), then Constitution (20) and finally Wisdom (20).
As a fighter you will get 14 attribute points in total while leveling up:

character lvl 04 + 2 attribute points
character lvl 06 + 2 attribute points
character lvl 08 + 2 attribute points
character lvl 12 + 2 attribute points
character lvl 14 + 2 attribute points
character lvl 16 + 2 attribute points
character lvl 19 + 2 attribute points
-----------
14 attribute points

You have the chance to gain +1 to Charisma within the original campaign (SPOILER WARNING):
by using Maferil's Lyceum: You need to make sure you have 20 Intelligence while using it!
Use a second set of items with +Intelligence or a strong potion and items to lift you up to 20 intelligence, then use the Lyceum and brew the permanent Charisma boosting potion (BLUE+YELLOW+GREEN is the combination).
Better save in case you screw up. If you can't hit the 20 Intelligence now leave it alone and come back later (the location will be on your map after you left Maferil's tomb.
This is a main quest, you can't miss it.


As seen below, numbers on the left count how many ability points you need to invest in each ability. When creating your character, invest your first points into Commanders Shout. Make sure to equip two Rapiers in the character creation screen as you can dual wield from the start.
As you level up - unlock Rally, Weapon Master, Improved Critical and Forceful Blows as soon as possible and get the first Ranks of Cleave and Hunter's Mark too.
During combat keep up Commanders Shout and Rally at all times.
In case you have distributed points wrong you can refund them - stick to this spreadsheet:

Battle Master (12 points)

1 - Second Wind
3 - Action Surge II
4 - Commanders Shout IV
4 - Rally III

Champion (17 points)

1 - Sure Strike
2 - Improved Critical
3 - Superior Critical
4 - Weapon Master III (more attacks per round)
1 - Steel Serpent
6 - Forceful Blows IV (render your enemies helpless)

Great Weapon Fighting (2 points)

2 - Cleave

Archery (3 points)

3 - Hunters Mark III (use on elites/bosses or to stop assasins from using stealth)

Protection (12 points)

2 - Shield Wall (while under heavy fire - swap to shield weapon slot, activate & return to dual wield)
5 - Bulwark IV (swap to shield weapon slot, activate & return to dual wield)
5 - Extended Defense (passive +2 armor class for you and nearby allies)

Shield Bearer (9 points)
Ability Tree is unlocked by finishing Jarhild's personal quest within the Original Campaign.

3 - Aspect Of The Mountain
6 - Unbreakable IV

Options for your remaining 4 Ability Points:
You can either boost the remaining ranks of Cleave or Second Wind, or if you want to support a party, put at least 1 point into Lockpick and Search (to unlock the Proficiency Bonus):

Great Weapon Fighting (0-3 points)

0-3 - Cleave II-IV

Battle Master (0-3 points)

0-3 - Second Wind II-IV

Skills And Proficiencies (0-2 points)
0-1 - Lockpicking
0-1 - Search

USE FOR LEVELING ONLY:
Riposte is very useful while leveling but looses value as you accumulate armor class.
Unlock it early and reap it's benefits but refund & reinvest the Ability Points later.

Two-Weapon Fighting (0-6 points)

2 - Whirlwind Attack
4 - Riposte III

Our weapon of choice is the Rapier with 2d8 damage (best finesse weapon).
Only use other finesse weapons if the enchantments make up for it temporarily.

Make sure to keep some alternative items with bonuses to Charisma&Intelligence or resistances as it comes in handy (Charisma&Intelligence is useful within the original campaign).

The following list shows you best in slot examples and alternative choices:

Weapon Slot 1:
Mainhand - Rapier
Best enchantment affixes are: vorpal (chance to insta-kill on critical strike), increased critical range, increased critical damage, vampiric (healing), +1-5 magic damage; usually you get 4 magic damage with another affix enchanted. Flat elemental damage is superior to elemental damage over time (because it only has a chance for the DOT(damage over time) to be applied and we attack so fast that damage over time is not what we want - we want flat damage increasements and above all high critical strike chance and critical damage, best paired with vorpal.

Offhand - Rapier "Swift"
Either you apply the same rules as above or you get the awesome Rapier "Swift".
Where to find that Rapier (Minor Spoiler Warning):
The shady vendor Burkins will sell it to you in Luskan (Original Campaign).
The Rapier Swift will double your action/attack speed, meaning the time you need to finish a round is halved. You will auto attack twice as fast now, more critical hits, more damage, it's impressive!
Just be aware you get a 30% vulnearbility to physical attacks (piercing, bludgeoning, slashing - we make up for it with high Armor Class and the Ability "Unbreakable").

I made a short video to show you the difference in attack speed while using Swift:
https://youtu.be/f7B7oIGjZIU
NOTE: Sometimes Swift stops working; switch weapon slots to fix it!

Weapon Slot 2
Shield - anything works, just use Bulwark, then switch back to weapon slot 1
Weapon - Ooze Bane bludgeon weapon or Elemental Damage Rapier

Armor
light armor
+4 armor class
+4 CON
+XX% Resistance or +X healing every X seconds
Example: Armor Class 1, +4 Armor Class, +4 CON, +75% Piercing Damage Resistance

Gloves
+3 Critical Range
+4 Dexterity, or +4 Armor Class, or XX% Action Speed

Helmet
+3 Critical Range
+20% Resistance (piercing against arrows)

Ring's
+3 Critical Range
+4 Dexterity, or +Armor Class

Amulet
Immune to Restrain and Paralize
+XX % Resistance, or +Saves, or +Elemental Damage (works only if your main hand Rapier has same Elemental Damage)

Cloak
+4 Dexterity
+4 Armor Class, or XX % Resistance

Belt
+4 Constitution
+XX % Action Speed, or +Elemental Damage, +XX % Resistance, or +Saves
I have not found any belt with +Dexterity or anything but +4 Constitution or Strength.

Boots
+4 Dexterity
+3 Armor Class

(all relevant changes have been incorporated within the main guide section above)

With the new patch we can now refund ability points!

New Shield Bearer Ability Tree:
The only Abilitiy really worth mentioning is Unbreakable, which gives us -4 damage on all physical attacks we suffer (slashing, bludgeoning, piercing), but it comes with a price (9 Skill Points).
This gives us even more staying power and it helps us to compensate the 30% vulnearability against phyisical attacks which we suffer by using the Rapier "Swift".

The other new Abilities:

Paralyzing Shout is interesting in the early levels but due to it's very low DC and the long cooldown I can't recommend it beyond level 10.
Aspect Of The Mountain is okay but I wouldn't invest anything beyond the first rank to unlock Unbreakable.

Debilitating Strike is just as bad/useless as all the other active damage abilities compared to our auto attacks.

Boundless Endurance is a joke: periodically heal 1-2 health for a big skill point investment? No thanks! If you want passive healing better get that XX healing in XX seconds enchantment on your armor or best a Rapier with vorpal and vampiric healing suffixes.

This update made us a little bit tougher - have fun with your killing machine!

Drow are now available as a playable race!

The Drow come with their exclusive deity "Lolth the Spider Queen"!
(this deity is only available to evil aligned Drow)

Drow have two Racial Abilities: Faerie Fire & Darkness:

Faerie Fire can be used to unveil invisible enemies (if they fail their reflex save), granting combat advantage against them (blue outline). This means in short: you get a bonus to your attack roll, which makes it easier to hit your target (if you want the long version, read it up within the D&D 5th Edition rule set). But as Faerie Fire has a low difficulty class (DC of 9), it's easy to make the save roll and to avoid its effect.

Darkness comes without a saving throw but you can blind yourself and allies with it too (standing within the area of darkness means being blinded until you leave the area. A blinded creature can't see and automatically fails any ability check that requires sight. Attack rolls against this creature have advantage, and the creature's attack rolls have disadvantage.
This is very useful to interrupt enemies which rely on ranged combat (casters and archers for example).

If you want to be a Drow, you will have to skip on the "Charlatan" background (if you don't, you will loose +2 strength and gain nothing from the +1 Charisma attribute boost in the long run).
Without the Charlatan background you will miss out on +2 Charisma and Wisdom saves, but being a Drow might make up for it. There is another viable background choice left in this case:

Background:
Outlander: +1 Constitution, -2 physical damage taken
This helps us to further compensate the malus we incur by using the Rapier "Swift".
You could pick other backgrounds (Hermit for example) but I don't recommend it.

Make sure your attributes are distributed like this:


NOTE:
You can gain +1 Charisma within the original campaign. To learn how please read the spoiler found in the attribute distribution section within the main guide above.

I hope you enjoy my guide and the new content of the community pack two patch!

Thank you very much for reading my guide!
If it was helpful to you, please like and favor it and make sure to check up on future updates.
Let me know if you have any questions or suggestions.

Noteworthy mention:
Sword Coast Legends' mechanics are inspired by the 5th Edition D&D rule set, which means it's not identical but the developers adapted parts of it. If you are curious about or familiar with the D&D 5th Edition, you can try to draw a comparison here: http://engl393-dnd5th.wikia.com/wiki/Fighter
Keep in mind: These waters may look familiar on the surface but they are not the same down below.

Enjoy the game!

Changelog:
16th until 19th of October 2015 - I created this character build during the headstart weekend
30th of October 2015 - finally shared the character build with our Community.
14th of November - updated the character build for the Community Pack One Patch.
5th of December - updated the character build for the Community Pack Two Patch.