The third book -- while not nearly as good as either Fire Upon The Deep or Deepness in the Sky -- had even more fascinating insights into the practical mechanics of a group mind with physical bodies. Like the fact that romance happens on two separate levels!

His first book Tatja Grimm's World was also about superintelligent people (or the whole rest of the planet except them was sub-intelligent, or something… it's not clear). That one is, hmm, not nearly as good as his later ones. So I think it's just as well he didn't try.