Increasing attributes is always a very good choice. I would choose feats only reluctantly.
Concerning Sorcerer (my main is mainly a Sorceress) we seem to have different opinions and playstyles, which is good. It's honourable to choose the weaker option with Draconic fire and throw the mighty firespells. Ok. I would indeed utilize the ability of the Sorcerer to put disadvantage for saving throws on targets and choose a lvl 5 control spell. I took +2 Cha at lvl 6 (I have two Cleric levels) and "Alert" at lvl 10. The most decisive factor in Honour mode is to go first, so initiative is very important and there are not that many items with a lot of + Initiative, therefore the feat. Especially as Sorcerer it's great to go first.
Shadowheart as Cleric of Light hurts me, I hope you gave her the domain only after her fundamental change. It's important to get her to 20 Wis anyway. In my party she has also the 18 Dex gloves for higher initiative and ranged combat (Clerics have bad damage cantrips).
The combination of GWM and Sentinel on Fighter is interesting. When I use GWM I go just for damage, so i increase Str as much as possible. More important than the damage number is the hit chance increase. The -5 is ok for Barbarians but a bad thing for fighters. I don't want my chars to have to rely on Bless. At least the Battlemaster has some means to increase hit chance.
Astarion I find a bit strange. Using a Str based approach for ranged combat is not optimal. I have this Str-based bow for my Barbarian, for a ranged Fighter there are much better options. Dex gives you initiative above all. Hand crossbows, sadly the best ranged option, use Dex. Crossbow Expert in my experience is a waste, a very weak feat (would be different if crossbows had the normal loading restrictions of DnD). Take Sharpshooter and increase Dex as much as possible, use some of the good heavy crossbows or hand crossbows. My current Astarion (I'm at lvl 10) is Fighter-Battlemaster7/Rogue-Thief3. Having two bonus actions is pure gold.
