Mitchell by a fair way for me.
Last year they averaged similarly, with an injury game for Macrae. Call it square, albeit Mitchell played more games.
Macrae' second best year is 107, then 100 and 100.
For Mitchell it's 119, then 105 and 104.
Mitchell has also played three years straight of 22 games, whereas Macrae has only managed one full season.
Worth flagging that both have changes in personnel in their midfields this year, and that both teams tend to rotateplayers through their mids - which predominantly represents downside risk for the very top scorers.
I recently added Mitchell though, and am reasonably comfortable with him overall.