Regarding shield bash perk – I think it’s not so bad, actually. Especially early game when you have no Rally The Troops perk. The strenght of it lies in reduced cost of fatigue as well as increasing fatigue for enemies. It is very effective when combined with bludgeon weapons to cause fatigue damage to enemies. Reduced fatigue makes it very useful if you fail the first one and want to use knock back once again to get additional chance to knock back someone (if it’s very important). Usually the “problem” about Shield Bash perk is not it’s weak bonuses, which to me are quite useful and I will sometimes pick it. I think increased chance to hit (10%) on perk would actually suit it more than dealing damage as you increase the value of your shield bash in a way that it becomes more reliable if you’ve chosen the perk. Maybe improved version could ignore shieldwall bonus instead? It’s just a suggestion, as I don’t really find this perk all that troublesome and I’ll sometimes use it.
Regarding AP idea on shield bash perk – I think it would become too much like stun, stun is unique because of how it works, it wouldn’t be a good perk design for lots of people, I think. Mostly because if something works entirely different based on weapon of your opponent – it is usually very hurtful for new players.
