I think covering the WU ranges with each color is a great goal! I don't believe the WU ranges affect potion ingredients though, as they don't have a WU number like the decorations and wall/floor skins do. ^^ I try to make the potion/evobar ingredient potion fairly often to send out with my pets so I can gather more of those liquid potions, but it all just kinda boils down to chance on what type of liquid potion the pets bring back. Unfortunately xD

For me, I tend to be a hoarder of the Velibolts and their evolutions. Raptors are my favorite, naturally. xD
I'm also trying to gather certain decor items, but I'm not doing much decorating/redecorating until I gather some full sets. Also, trying to work toward a bigger house. My goals are not hard core though, and I'm mainly just having some fun and waiting for the Adventure to roll out ^^ When that happens, I'm sure some new goals will emerge!