Oath of desecration is 40%, it also costs 3 AP. Power stance is pretty minor (only 20%) but it costs 0 AP. They all stack multiplicitively if I'm not mistaken. At release, power stance increased the AP cost of attacks by 1, which it no longer does.
20 armor is actually fairly significant because of the way armor is calculated. About the first 80% of your armor doesn't do a thing except get you up to level. Imagine you had 100 total armor and that resulted in 50% damage reduction. At 80 armor, that damage reduction might well be down to 1%, and it will stay 1% all the way down to 0. It's a really strange system they have and I don't know the exact calculations, but it means that a small increase or decrease in armor can mean a fairly substantial difference in effectiveness, which is necessary for things like iron hide or armor specialist to do anything at all.
Not that it matters if you have 0 armor when your enemy is knocked down or dead.
Anyway, they all needed adjustments and I won't say just where it would have been "right". It is however NOT right where it is now. They nerfed an entire mechanic to uselessness, but left the core problem in the form of other abilities. If they had no plans to actually fix the problem it would have been far better had they left sneak completely untouched. As it is we have one fewer mechanics to play with and the game isn't any closer to being not-broken.
