29 years is a long time, and I don't like to get rid of things.
All of my basses are 4-string. I just have never gotten the 5-string bug. 2 of them are fretless.
They're like crayons. Everyone has a different color, and I like them all.
I have 4 main basses that I play out. 2 Squier VMJ's (one Fretless), a Rickenbacker 4001, and a Spector NS20004. I'm probably getting a Spector Coda, fretless, for my new main bass, as I seem to be almost 100% fretless these days.
But, I could get bored and change my mind.
I've heard over the years a lot of TB'ers saying "I only need one bass, purity purity purity" but the fact is, I'm not doing this for anything except having fun. So sometimes it is fun to have a new bass.