Alembic.
Now, I'm speaking as one who has played for a long time, but semi-professionally at best and near zero studio time. So I play what I want, not necessarily what a band leader or studio tech is looking for.
I like Alembic because they are top of the game in terms of build quality, craftsmanship, quaility of materials, and options. They are pricey as all heck (buy USED).
Alembic invented active circuitry in basses. Since they build their instruments, their electronics, their pickups, their bridges, it all works when it comes together. The only things that they buy are tuning pegs and strings and maybe their knobs. They have a very flexible tone palette (due to the electronics) and are very powerful in a live situation.
I've been told that studio techs HATE them because it's hard to dial them into the mix. Especially if you are trying to make an Alembic sound like a P-Bass. Of course, in my opinion, that's sort of like trying to make a Corvette sound like a Corolla.
As far as more MAINSTREAM brands, I'd have to say that Music Man would be my favorite. Just love the tones you can get out of the Bongo in particular. If you can get past the looks, it's HOT. For that matter, don't sleep on the Music Man Big Al. Three pickups and out-of-this-world electronics and tone controls. Maybe even uglier than the Bongo, but killer tone.