Creatures Caves

It really, really depends a lot on what breed you're using and what kind of run you want. Is it just meant to breed as much as possible to produce mutations? Or is it meant to weed out weaker individuals and be a sort of survival of the fittest thing?

Meanwhile, there are other considerations too. Swimming breeds need aquatic rooms, obviously, but they also tend to do better with wide open rooms like Artemia Sea rather than enclosed rooms like Aquanornia, which work better for non-swimming aquatics in my experience. (Both types can use either room and be OK, that is, but the wider rooms are specialized for swimmers and vise versa, so they tend to give better results.) Same goes on land for flying breeds versus normal walking breeds.

You will want to scatter some extra toys and food, but how much is up to you, depending on how difficult you want things to be. It's also up to you whether to add weeds and similar 'traps'.

So it's hard to make recommendations without knowing what you want! FWIW, I do feral/wolfling runs almost all the time and these are my preferred metarooms:

Aquatic/Amphibious for swimmers - Deep Abyss, Artemia Sea, Hydro Nornterrarium, Past Seas (only to 'steal' its plants and critters for other rooms - it's a bit too small), both Aquatilis Caverna rooms, Devils Reef

Aquatic/Amphibious for nonswimmers - Aquanornia, Hydro Nornterrarium, Past Seas

Land (rooms good for flyers marked with asterisk*) - Biodome*, Veridia*, OLSA, Silence Falls (small but nice; too small to be great for flyers, but open enough not to be a problem for them, unlike, say, OLSA, where they really don't do well in my experience), Nornhulu (again, small enough to be better for walkers, but open enough to be used by flyers), Norngarden 1*

Not everyone likes C1toDS, but it's a good compromise room, as it has wide open spaces for flyers, two good-sized seas for swimmers, but is designed, of course, fundamentally, for walkers. So it has reasonable spaces for most breeds.

Note that highly specialized breeds will require specialized keeping even beyond this. For example, Frost Norns and similar will probably have to be kept in Chione or another cold metaroom.