3)The longsword was not a two-handed weapon. I think there are already plenty sword types in the game, but maybe the falchion could become a weaker war cleaver and the longsword could take its place.
You are wrong, it’s very agile and fast two-handed weapon, of course you can fight with one hand but you’ll lose all advantage, and there are some techniques with only one handed attack.
Check this out https://www.youtube.com/watch?v=3fK35jaxf8I
6)Instead of higher AP cost, I would add more fatigue with each reload, so you can still fire one shot each turn and reload. You’d just tire faster.
Heavy crossbow requires windlass or cranequin to draw, it’s not very tiring but it require a lots of time so 9 AP is more realistic solution. https://www.youtube.com/watch?v=8J3qMzQlITI
12)Two-handed warhammers would be cool, as long as they have an respective high minus on the max. fatigue.
I’m not talking about heavy fantasy two-handed warhammers, I’m talking about this https://www.youtube.com/watch?v=92_TKngfYFQ
It’s not so heavy as you can think.
13)Tripping enemies. How different would that be from stunning?
It could decrease enemy AP and gives bonus to hit him.
There will be more monstrous enemies added later.
I know but I’m talking about every supernatural creature like all undeads and verwolfs. Morale and panic efect could be use more often.