also i should note that if unit caps were introduced, those units would get potentially buffed depending on their unit type, like Dark Templars for sure would get buffed.

I'd say keep them as long as they fit the medieval theme of Bretonnia. I honestly think keeping Bretonnia strictly to tabletop and not to what makes sense in a medieval army like dismounted knights is rather boring and makes them suffer as a faction compared to the other ones in game.

I'd say keep it roughly close to lore accurate but don't be afraid to branch out a little bit for the sake of making the faction more interesting.

For example: They don't need heavy cannons or steam tanks, but crossbows wouldn't be too far out there

Could you add a unit similar to to the Genoese crossbowmen? They were a mercenary group employed by the French against the English.

They used giant shields (called pavises) as cover while working with three man teams to maintain rate if fire while shooting.

Stats could be similar to the Jade Warrior Crossbows or Celestial Dragon Crossbows from Grand Cathay, but with higher armor and less melee capabilities. They were archers not fighters. Since they were professional mercenaries they could make them cost more/higher upkeep or put a unit cap, since they don't make sense as peasant units. Two turn recruitment since they are being hired from a distant land.

Jade Warrior Crossbow stats:
https://totalwarwarhammer.fandom.com/wiki/Jade_Warrior_Crossbows_(Shields)

Celestial Dragon Crossbow:
https://totalwarwarhammer.fandom.com/wiki/Celestial_Dragon_Crossbows

@STR4ANGER_D4NGER sounds like a good suggestion, ill add it to the list, currently modding has been put on hold of the past 3ish months unfortunately because Asset Editor used for making the models is kinda messed up and unfortunately none of the work arounds are working for me, so kinda just waitng til an update comes out for it. but to me it sounds like you are asking for a unit similar in function as the Dark Elf crossbows with shields, yes?

I haven't played with Dark Elves yet (only had the game for like 2 months) which is why I was referencing Grand Cathay. Pavises were huge wooden shields that were more like barricades, probably about the size a a door +1/2 and were set on the ground when in use rather than carried by a single man. Think the stereotypical rectangular roman shield but bigger and carried by the whole team.

@STR4ANGER_D4NGER OH ok, i somehow misunderstood the whole '3 man crewed pavise shield' thing. well anyways I can make the crossbow troops with a single Pavise for each soldier, but creating a large pavise moved by 3 troops is outside of my modding capabilities as that most likely requires me to alter animations which i dont know much about sadly, and to create some sort of "vehicle" styled unit where the 3 troops would push the pavise and then engage with crossbow when in range, which is sadly also outside of my modding capabilities, BUT I'll still keep it on the list cause I am still learning everything i can do with modding.