Eddie's a backup plan if Nate costs too much to keep around.
I'm hoping that they can keep NateRob around fairly cheaply. Not a distributor, but that's less of an issue for the backup, since he's usually not going to be playing with the team's best finishers. Love how he was playing D in the playoffs; if TA really IS coming back, he and NateRob can potentially just destroy other teams' second-unit backcourts. Doesn't shy away from the big moments.
NateRob's more likely to win us a couple big games than a "safer" backup like Earl Watson.
Eddie House, unnecessary if Nate returns, but does force the D to cover him and i think often got a bad rap. I'd be surprised if he DOESN'T land in Miami, though; he'll be cheap, he's played for a lot of teams but for quite some time has been pretty selective about only signing with pretty good teams. He's played in Miami before (although, where HASN'T he played?). Would do a great job at keeping the defense honest, and his weaknesses as a ballhandler are rendered almost completely moot if he's playing alongside Dwayne Wade and LeBron James (both of whom often are de-facto point guards).
Hell, Eddie House could probably be the starting point guard on that team. He's just got to get the ball up past halfcourt, get it in the hands of DeBron, and fade to the corner.