If you don't play without a pick much, I'd suggest trying to develop your finger style. I'm not starting a whole pick vs fingers thing here, I just think it would help you loads if you were proficient with both
If you're picking stuff up by ear then that's good, but keep working on it. Try transcribing harder and harder things, and not just bass lines, try some of the horn melodies and solos if you like ska music.
And starting out in jazz never harmed anyone

You say you've learned how to play complex walking lines, is that learning other peoples or improvising yourself?
If it's learning other peoples, then use those ideas to improvise your own lines. If it's your own, then carry on with that, and maybe start some soloing. I know that's a bit vague, but check out the
Aebersold series for loads of great stuff
Hope that helps
