I feel like the format of PZ2's DLCs would be a lot more interesting than the contents themselves. I'm gonna say it; they should be bigger. I propose that PZ2 have three DLC formats:
Animal Packs: 9 habitat animals + 3 exhibit animals
Scenery Packs: 6 habitat animals + 2 exhibit animals + building theme
Expansion Packs: 20 habitat animals + 5 exhibit animals
I don't care if it's a realistic expectation or not, the sequel cannot have the same DLC format as the first game.