I don't think that, as a planet, those worlds are nearly as interesting as the top four. Scadrial was specifically designed by Ruin and Preservation in a deal that let it be destroyed at a later point. Roshar has highstorms, greatshells, and a super-continent based on a Julia set. First of the Sun has a symbiotic relationship between psychic bacteria and birds, and predators that have evolved to track prey by their thoughts. Taldain is a tidally locked planet that somehow can support life on both sides without them freezing or burning. Sel has some interesting stuff realmatically with the Dor, but that's it. And we only know about one city on Nalthis; as a planet, it seems kind of boring from what we've seen so far. No dangerous, giant creatures trying to kill you.
Thanks! Although now I suppose I should find something else to support.