Ahh.. Guppylover was correct, Silver Dollars are too big, and Discus really should be in a larger tank. Also, discus need perfecto water, and thats harder to achieve with smaller sized tanks with large fish in them.
Anyways.. Im not quite sure if a gourami will go well with angels, but if your tank is atleast 18' high, then it would be perfect for a few angels. There are so many different types and colors.
If you DONT go with angelfish, a nice school of neon tetras or cardinal tetras would look gorgeous. I
think that 15 or so would do nice in a 29 gallon tank, with frequent water changes. But if you want alot of other kinds of fish, I suggest cutting that number down alittle.
Hmm.. lets think.. hmm.. Corys are cute, and you could put a few in there. Hmm.. basically the only nice things I can think of are neons and most definately angels. I'd go for a few angels.
Good Luck!

Dakota