Tom has given good advice as usual. Keep in mind he's a pro; I'm commenting as an amateur/semi-pro (my day job is in something else, but I have been to music school, can read music, arrange, analyse charts, etc etc.
That said, I would simply suggest transcribing what you enjoy. I also tried transcribing people I wasn't fussed on and it was a waste, although they were part of the 'canon' of things you were meant to study. But I do best when I find something that catches me and makes me go 'hm...gotta learn how to do that'. The instrument doesn't matter.
Have a care that you don't HAVE to transcribe the whole song or the entire solo, although again it's good. But take the bits you like for sure.
Overall, I will simply say I have become much less bothered about the process of writing out what I have learned - though it's still good to do. I now consider it best to be able to sing the solo, learn how to play it on bass, understand it as best I can in context of the chords, and then finally write it out. Even then, I consider it more important to use the bits I have learned (try them on tunes, put them in all 12 keys) than I do to committing it to paper.
Just my 2p
Pete