I suppose that's a difference now yes, even if the change is for all units so their remain balanced the same, if fights can go quicker, it's harder for the player to make a difference.

The avatar is strong, but within reason still. There's a reason behind the units you can get in lvl20 of the original campaign, you don't get mistresses or vampires, and skeletons you could technically get but are unlikely because of the better alternatives and as such the unit composition the player gets makes sure the avatar lives for quite a bit. While 10 dragons and 10 biles are powerful, against a single unit they are nowhere near as effective as say, 2 dragons with 10 mistresses would be. If in this AK level you feel they are under powered, they could get a stat boost there of course.

Escaping at the moment only happens when a prison neighbors an enemy room. Or I guess if you fight witches.