Agape, I think 30d6 Assassinate is fine as long as it's not too easy for the Assassin to fulfill the Assassinate requirements, which I will endeavor to ensure in PSW III. Anyway the attack still doesn't kill Masters outright so it's hardly broken.
There're actually very few ways to increase SR.
I agree that a mount should be an innate just because it's Rider but I am loathe to deal with it now so I have decided to leave it in the hands of whoever hosts PSW IV.
AG, your first concern is very valid. I'll reduce the destroying bonus to 50 and raise the basic amount gained to 150 per day then. Do not worry, I will scale ability costs accordingly.
Regarding the award system - there's nothing wrong with your point, I just don't like such a method because I feel it is inelegant :P I am likely not going to include such a system now anyway.
Berserker will still retain his d12 hitdie. You can interpret the class as Barbarian but like the other classes it still won't have its other class features like Rage Powers.