+25% less recoil
+more damage closer enemy is to shotgun (thnx fantasyrow)
+50% closer bullets

-25% damage penalty
-25% fire rate

+20% more damage
+20% more pellets
-(4 shots only)
-20% accuracy

+More accurate
+30% faster reload rate
-15% fire rate
-65% clip size

+ 15% to accuracy
+ 10% to damage
- 20% to fire rate
- 33% to clip size

+40% more accurate
+does 30% more damage at objectives and defending objectives
-10% less ammo
-does 20% less damage any where but objectives

+%15 damage
-%80 pellets
Causes knock back on target
+1 clip size (7)
-%34 reload speed
Increased knock back on airborn targets

+30% more pellets per shot
+20% damage
+50% attack speed
-68% clip size
-70% range
-25% reload speed

Short, balanced, and interesting stats:

(!) Max of 45% Accurate

Pross:
+15% Accurate
On kill: +5% Accurate (Up to 5 kills, or +25% accurate)

Cons:
-50% Clip size.

+ambassador anti-spray over time mechanic
+25% more pellets

-33% clip
-25% fire speed
-10% aim boost speed

simple enough right?

+20% accuracy
10% faster firing speed
-34% clip size

+25% Damage
+15% weapon switch

-30% Reloading speed
No random crits

The Steady Shot
Level --- Shotgun

+20% more accurate
+10% ammo size
-20% clip size
-No random critical hits

+ more bullets per shot
+ less bullet spread
+ 20% switch-to-speed and 15% switch-from-speed
+ Alt. Fire: unload 2 clips at once with less accuracy
+ 10% - 20% reload speed
- clip size from 6 to 3 (before you have stop to reload dont know how it is called)
- 10% - 30% less damage
- 20% slower firing speed
- while you are in the air you get marked for death (minicrits)

If you like these stats contact me with a steam message
Hope your weapon gets in

How about...
Hold M1 to charge shot, no base charge rate
takes 5 seconds to fully charge
Deals damage to sappers
higher charge increases accuracy
10% Damage penalty
20% Fire rate penalty
No random crits (Just for balance's sake :P)
fully charged shots crit

Stats:
Smaller bullet spread
-25% vulnerability
+30% accuracy
More pellets per shot