ive been playing bass for about 6 years now, and im pretty good. ive taken lessons, learned and absorbed everything i ever could to make me a better bass player, and practice all the time. but i feel incomplete like i should b learning more or b bringing my bass playing to the next level. how can i bring my bass playing to the next level?
Well, if you havent allready, Id look into complex rythmic stuff like odd time signatures and polyrythms. And learn a new genre of music, if they are any you havent tried yet
Assuming you already play with other musicians and perform regularly:

I say six years is a good time to develop laterally instead of vertically. Expand your horizons with new genres, by composing more, by getting much better at theory or a secondary instrument like piano, gutiar etc. or a secondary musical skill like recording/mixing/building, etc.

All of these things will lend extra insight to your bass playing, and will just make you an all around better musician.
If you think of your knowledge as a wall... you are building a very, very long wall. You are good at lots of different things. The wall is wide.

Now you need to make the wall high.

Can play some harmonics? Good. Do you know what note each harmonic is? Can you play a scale in harmonics? What fretted notes work with Harmonics?

Know a bit of Jazz? Can you get a chord sheet and improv a jazz line? Do you know lots of popular progressions? What chords are used in Jazz a lot?

Play your scales? Can you play them over two octaves in thirds? Know what every single note on the neck is off the top of your head? 15th fret a string (dont look)?

What about chords? Give me a g7, an Em.. ?

Build the wall high.

Thank you so much applehead, I've only been playing a year and a half on the fifth but that's given me a reason to start really getting into my bass playing again.
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