At some point this year, one of our three rotation bigs will be out for a few games, and Yabusele will get to play. I'm confident that he can do anything Baynes can do and more. He just needs half a year of rotation experience to get there. I'm not worried about Baynes. I'm more worried about Theis, who I think is already better in many circumstances.
Marcus will not be here next year. He has two roles on this team. He serves as the second team point guard, and he also serves as the 5th guy with the starters in certain spots, particularly at the end of games.
He is useless as the second team point guard, because he does not have the ability to create with any consistency, he cannot shoot when covered, and he is not a particularly good decision maker.
He is quite useful as the 5th guy with the starters. He servers as a secondary ball handler, but he doesn't have responsibility to break down the defense. Teams cheat off him, and when he gets a shot, he's much more open. He's the last option, and his primary role is to be opportunistic off the ball, which is his one elite offensive skill.
Unfortunately, that just isn't enough to pay the man good middle class NBA wages. He needs to do both to stay ready, and he is so bad as the second team point guard that he will inevitably lose that role whenever the team comes up with a viable option, which is inevitable.