I would keep him on normal rotation now.
I want Barlow, Brace, Roedig, Shirah and Chapman to pitch more. I really like what I have seen from these guys and they are probably going to be the pitching core next year. I wanted to see more of Mannelly this year, but somebody said that his arm was in a cast so that explains why.
Bartnicki has excellent stuff, he just needs to learn to pitch at this level and it typically takes a freshman pitcher an entire year to get his feet under him. The most important thing I look at for freshman pitchers is strikeouts to innings pitched. If they have more strikeouts than innings pitched, they are going to develop into their potential.