About anihilate and its critical chance. Considering the fact that anihilation, has anihilate as main skill, and dots overall, you need your critical chance as high as possible. We need crit since it is about the low hits if we do not crit.
Pointing out you need past 32% critical in your melee attack to make anihilate an efficient build. You could stack power and have a low grade crit chance, so even tho you do not crit, you have a decent amount of dmg output, but mostly it is not about having your main skill crit, it is about your dots criting, why? because having your dots crit will grant you a self heal of your max 2% hp, if you get a constant crit on your dots, they will add up nice dmg + self healing you, wich will sustain you along the fight for more time. Surge is vital aswell, but not over de edge. Surge should be kept at 75% since it is decreasing horribly after the 75% barrier, it is a waste of stats adding further surge afterwards.
An anihilate marauder should look like this. 102% accuracy ( would be wise to get the accuracy passive skill from carnage tree) above 30% critical unbuffed ( for a good chance of having your dots crit and heal up for it) and a 75% crit multiplier (inflicting more dmg above).