Actually, at 59 Shadowstep would most likely be your best bet. 50-59 is the only bracket where it really shines. Also, at 59 there is absolutely no resillience that I am aware of, which means you can go daggers also and do some major ambushes. I, personally, would suggest nothing else at 59.
Something like
this would be in order. You can swap a few things around if you like, but that is what I would do.
As far as the 49 bracket is concerned, I wouldn't suggest BGing here for too long for the simple fact that you have no 41 point talents.