I'll preface by saying i know nothing of Branch or his game other than what i've read here. Nuri was a better basketball player i think, definitely a better scorer. He wasn't a good fit here, which was proven by the staffs' and his decision to part ways after 9 games. Comparing each players stats is useless in this case. Branch seems to be a true PG, who sets up his teammates and plays exceptional D.
This team, with D. Harrison and Harkless as the main guys, have scoring punch. What we lack is someone who has the ability to get the ball to these guys on spots on the floor where they can flourish. This will also be a tremendous help to GG and the rest of the gang.
Just because Nuri could beat Branch in a one on one, doesn't mean he's the best fit for this particular team. Hopefully Branch is. If he can score 10ppg, great.