I don't think the sample size of Chavis is big enough. Marco's is fraction of MC's.
Chavis is at .702 since May 6th. That's 281 out of his 344 PAs this season.
Chavis & Marco still have a lot to prove.
Look, I've said all along I'm for not signing any right side IF'ers this winter. Let's save some money and go with Chavis, Marco, Dalbec, Chatham and Lin. Maybe bring back Holt, if he does not cost too much. If we end up competing next year and need to upgrade, we can deal with that at the 2020 deadline.
My point is that we should not count on either of them as sure bet ML'ers, let alone pluses this early in their career. Chavis's offense would be a plus at 2B, but he has to improve to be a plus at 2B. Marco has to prove he can stay healthy AND hit well enough. He's doing well at AAA, now, so there is hope, but he is far from proven.