I think my '76 Thunderbird is still the bass for me.
I always wanted a Thunderbird, but I didn't knew how it played and sounded. There was one in a local shop for cheap, but it was battered like hell. Holes where drilled for extra switches, a piece of wood was nailed (!) on the entire lenght the body as a finger rest and I think they used it in a Robin Hood film as a bow. Of course strings where dead, and it had a lot of issues. I still bought it and of course it was a major dissapointment. I had someone to fill up the holes, but it still sounded and played bad. Then my luthier took care of it and.... Wow! It still is the worst looking '76er around, but it's totally my bass. I do all the recordings with it and I actually feel better and I feel more secure playing that bass. I feel like a GI in an old war movie having an M16 at the hip and no one ca do anything to me:) I'm just more myself with that bass. It belongs to me. Of course some mojo is added by one or more previous owners, but I did too:)
It stays better since an unknown sugar uncle send me a 70s case for it:)
If I had to sell some of my basses, of course I would feel bad. But I would be happy with only the Bird and maybe a cheap back up. (BaCH).
The only time I felt totally okay with a bass was with Uwe's blue nonrev. I dunno why, but that bass felt immediately good too. The BaCH comes close, but of course it has a lack of mojo which will come over the years.