Yes there are a lot of abilities, but it is definitely situational. For instance, if I'm soloing with my companion I'm probably not going to use crippling strike. If I'm fighting an easy enemy I likely won't use ravage. It really all depends. Personally, I've found a core set of skills to use for questing, grouping, and pvping that I like and find to work effectively. It just takes a lot of playing around with.