I went from many years of 4 to a few years of 5 - and was seriously thinking of going to 6 when I decided to go back to mostly 4.
I noticed I was playing more and more notes on the 5 and starting to get too much away from what I think I should be doing in my role as a bass player. On the 4 I was primarily sitting in the pocket and laying down the groove. On the 5 I was tending to get more... I don't know... 'orchestral' or 'busy' maybe?
That's when I figured if I wanted a different role maybe I'd better break my promise to myself and pick up some guitar instead. (I started on string bass before I went electric. I never was a guitarist.) And I found that to be a lot more satisfying a way to scratch that particular itch.
I do want to do more with piccolo bass however. I always thought a piccolo and regular bass would be a potent combination in a band. That 'cello' range isn't addressed all that well in my opinion. And the baritone guitar is just too overwhelming in most settings. So I'm thinking one way to address it is to add an additional instrument, with its own musician, to the mix rather than keep adding strings to an existing one.
This is just me thinking out loud however. I'd also guess most 5-string players won't share my concern about overplaying. In a completely different musical framework than the one I prefer to work in, playing more (and more!) could well be a positive and desirable thing.
Like everything in the world of electric bass, YMMV.