There are plenty of managers that had shitty winning percentages before they finally got a good team. Joe Torre had some less than fun stops with the cardinals and mets before he was granted the Yankees unlimited spending in the 90s.
It's hard for me to quantify how much the cheating affected the wins for the astros, it definitely affected it but to what degree? The team was and remains competitive, although I think this season was extremely strange and hard to judge what effect the cheating had on the team. I certainly don't think less of your opinion of him, because neither of us really know what was happening the entire time.
like I said before, a move like this certainly isn't one to brag or be proud about, but I feel he is a good manager based on how he handled his team, his bullpen, in game moves, how hard his players played for him. A lot of this is anecdotal on my part, but I'm no astros fan so I can only judge what I have seen