I'm not really a gear enthusiast , only own budget gear, and don't have an upgrade path in mind.
So off the top of my head and within the rules:
Bass: I'd get a top of the range Fender Precision
Amp: I'd get an easy to carry Markbass combo or somesuch.
In real life, as some others have said, I would prioritise aquiring a sound-proof music making space of my own. Then fill it with my existing gear plus some budget stuff to fill the gaps ........... drum kit (acoustic if the soundproofing is good enough, other wise mesh electronic), Lap top,a few mics, small budget valve guitar combo - all aimed at home recording, or having people round for a jam.
But probably would not care much about getting any top of the range stuff (at least that what's I think now.... but once the money is burning a hole in my pocket, who knows?!)