So I've been playing electric for several years and use it for my jazz gigs along with my upright. I have a couple regular gigs with a big band and a combo. I recently purchased a custom, expensive fretless bass which is my go to. I've used it for every gig since I got it because it's such a great bass but I thought by now my playing would be more solid. I've had it for a few months and I'm still having trouble with intonation, especially in the big band where it's not solely improvised. I have a fretted j bass that I used for those gigs until I got this bass but it's not the greatest bass. I'm thinking about moving the fretless to somebody who's better with it and getting a fretted but I'd feel bad, I got a great deal from the maker and it's still an incredible bass, I just wish I could play it more reliably. Thoughts? Suggestions on how to improve fretless playing? I'm mainly an upright player and don't practice electric daily which is part of the problem but I just don't have the time unfortunately.