He'd probably be are best two guard as well.
I see it like this, Thomas plays about 30 mins per game, so give Dunn 18 mpg as the back up point and let him run the team.
Play him an additional 12 to 18 minutes at shooting guard and there is your 30 to 36 mins playing time. With his Defensive versatility you could play him at Small Forward if needed.
Still have to trade either Smart, Bradley, or Rozier for a big, but that's what's best for the team anyway.