Strings, string, strings!
I only play 34" for my 5'ers, I don't care for the feel of 35's nor anything longer than that. The quality of the B is what was I discovered it boils down to over the years, and I like bright tones with piano-like attack. I can get along with just about anyone's 4 string sets...these have been made great for decades. but B strings didn't feel as tight in the 90's, but many progressively got better as production techniques got tighter over since the 2000's.
My two favorites are DR Hibeam/Sunbeam and then EB Slinky. I've also used Galli with excellent results. D'addario B's is very decent, but I don't love their feel. I cannot get long with any of GHSs' strings. And while I love R Cocco 4 string sets, their B strings are terrible, flabby, and the tone never matches the E-G strings.
I have custom Wal 5's that are of course fantastic, as are my StingRay 5's... but you should try my cheap Squire Jazz 5 thats loaded with Galli 40-125 rounds and my own set-up work, you'd think it sounds and plays like a $2k bass!
I use 125 B's if I'm standard tuned, and if I get hired by a band that tunes 1/2 step down then I'll go to a 130 B