I've always looked at "music education" like a many-legged table where each leg is an aspect of the learning. If all you do is learn how to play an instrument, but not why or how to maintain said instrument (for example) then it's like one leg is long while the others are too short and your table falls over. I think you need to learn some of one part, then some of another, etc. before you go back to expand your knowledge on the first part.
Depending on just how far you want to go, you've got music theory, perfect pitch & relative pitch, harmony, instrument knowledge, instrument playing (which is different), instrument maintenance, amplification, gear (& effects), mixing, recording, how to gig, and how to integrate with other musicians. Note that when I say "instrument" that could include your voice! (Or a turntable if you're a DJ like Zo! ? )