Yeah, we know how big the balas get, but my husband really really wants one. So I told him we can only keep it till it gets to 6" then we have to find it a new home. But the LFS said they were okay by themselves, and I've seen them in friend's tanks by themselves (not in a school).
The research I've done on dwarf gouramis says they need to be in a school of at least 6 with a 2 females for every male. And they are always in schools in the stores, I don't see why they wouldn't get along in the tank. Like I said, I think the main problem will be them will be the beta.
The crayfish seem to be doing okay so far, they haven't really had any problems...but I don't know how to tell since I've never really had one. The temp is 75-76 and the LFS said they would be fine. Once again, though, I've never had a crayfish and I can't really find much info on them.
We have some plants and caves for shy fish, but since I've just started the tank up I didn't have the $ to add as much as I wanted. I'm going to get more to fill in space in the back and along the sides...I'm pretty sure the gouramis are shy, and I already KNOW the crayfish are. If you go to the Rate My Tank forum and go to my post there are pics of our tank...let me know what you think.