It would help players with weaker serves but on the flip side
would not give them too much incentive to improve their serve.
I still predict 90% of the time in doubles the winning team would
elect to receive the next point and in singles close to 100% would
elect to serve the next point so the game should not slow down
at all. If anything, would speed up the game due to more players
may work on return of serve and picking the serve. It would be
interesting to see every once in awhile where they choose the
opposite. Also who would make the decision.. The server? What
if the server was a rookie paired with a 10 year veteran in the
back. Would the backcourter override him?