I chose "aberration" (and there's NO excuse for a DM to not be able to spell that -- it's what half the fun monsters are!), but really it's a homebrew with a LOT of external influences. I steal what ever I can to lower my workload, especially from the Manual of the Planes.
I went for the 'aberration' choice - homebrew with items dropped in from many supplements, including Freeport: City of Adventure, Bluffside: City on the Edge, Arcana: Societies of Magic, Assassin's Handbook, Book of Fiends, and others.
None have made it into my world unscathed, though. I never feel constrained by what's in the book, and cheerfully change things to suit my needs.
I use a lot of supplements, in a frothing mixture of delicious campaign yum.
BUT, I do pick and choose some things based on the flavor of the campaign I'm thinking of running. For instance, in my postapocalyptic setting, I use some harsher house rules for death (such as a lower massive damage threshold) that I don't use in my "regular" campaigns.
I call my style "kitbashing". I've used Al-Qadim, Dark Sun, Ravenloft, Living Jungle, Citybook, Hollow World, Freeport, and assorted other goodies. Oh and you might detect a hint of Edgar Rice Burroughs (no kidding), Steven Brust, HP Lovecraft, Fritz Leiber, Stephen Erikson and Glen Cook scattered here and there.
I didn't pick an option because none seemed to apply. Barsoom is everything I think is cool, just about.