Which pack should I get next?

Of those 4 choices I would go with Jungle Adventure. First of all, GPs just add more to the game. Second of all, if you were really into vampires, you would already own the Vampires pack. The vampires are well made, but it's just the world that came with it is tiny and vampires can be a bit annoying. I don't even mean the very rare break-ins, but the vampire visitors that knock on your door late at night, lingering for hours and keep the game from switching to super-speed when your sims are sleeping. And JA gives your Sims a nice break and archeologist can be like a freelance career if you register yourself as such with the Ministry of Labour and make your money by selling the artifacts you find in Selvadorada. There are new dishes, two very nice new radio stations, new dance moves, new harvestables ... it adds enough to keep you busy for a while.

Regarding the stuff packs, as someone who used the washer/dryer in the game in one household only (I have +40 active households at any given time), I still have to say it is a good stuff pack. BB and CAS are very well done.
MFP is out of the question for me, never going to spend money on that one.