For me, #1 is need. Once need is established, then I'd rank price and playability, then looks and tone. Lots of things can be done to affect the tone, besides it will always sound different at the sale location than with my setup. I could always refinish it and even reshape it some to my liking. So I go for cheap/DIY ones that I can tinker with.
That being said, having not reviewed the tons of basses that are out there, if I had to choose the best looks and tone and not mess with it, it'd probably be a Spector.
BTW my great uncle built a playable toilet seat bass back in the 70s. Next time I go thru the attic at my dad's I'll hopefully find the pic of it.