There have been various long range plans to run the Brown Line west along Lawrence to Jefferson Park, meeting up with the Blue Line there. I'm not sure how much that would help the far north side/Evanston though as you'd still have to go down to Belmont before heading NW.
Ravenswood is booming and this would make it easier to get to any part of the north side south of Lawrence, but it will cost billions to tunnel under Lawrence (no way they're going to build new el through residential neighborhoods).