I rather like stalkers, and as you grow in level you'll be looking at all the powers. I don't worry too much about builds, I just throw any purple sets that are available into them and seem to do OK.
Builds are great, but this isn't Diablo. We don't have to worry about clearing pit levels at increasing difficulty. The hard part of stalkers is trying to work out the best place to slot the stalker ATO's so the chance to hide proc is most useful.