Happ - No concern, he has been good for too long, and is showing signs that a heater is around the corner
Mastrobuoni - Little concern, he's a bench player and I'd expect him to be stronger with the bat going forward, but ultimately he's probably not among the best 26 on the roster so I'm not going to hand-wring his minutiae. This series was bad but far from what I'd expect as a norm.
Madrigal - Mild concern, similar to Mastrobuoni he's not of incredible importance, but continuing to not square the ball even with regular playing time makes him a rough profile. I've long stuck up for Madrigal because people exaggerate his shortcomings since no one apparently can accept bench-level production on the bench, but he and Mastrobuoni on the same roster isn't a long term solution.
Busch - Little concern, you have to give him the runway to keep making adjustments, and even when he's struggling he's working counts and making some contributions. Anecdotally I haven't seen any defensive misplays in a spell too.
Hendricks - High concern, he can't keep rotating between decent start, unlucky disaster start, and deserved disaster start. Part of me hopes that if his next start or 2 doesn't go well, that he truly gets rocked, because I think he can probably right the ship to some degree, and if he admits that he's not playable right now I think he could be agreeable to working things out in Iowa.
Morel - Little concern, taking great at bats, tragically unlucky batted ball luck(.376 xwOBA). The defense is what it is, it's not good and not going to really get much better, that's okay given the at bats he's taking now
Amaya - Medium concern, there's no real smoking gun that I can see but the unplayable offense stretches how much you can give him runway to succeed, especially since his MLB/high minors track record is not long.
Gomes - High concern, I think I was early on the possibility that his bat is cooked, I don't need him to be last year offensively but if he's gonna be a slider speed bat he needs to punish those, because a 32 wRC+ stretches how much you can value defense from the position, doubly so with Amaya in a deep funk