I suspect you're probably right. Ideally I'd like to at least get rid of Edwin and Kat, eliminating the main negative influences.
I'd wondered how the MC would deal with it if/when his mom and Mina found out, since they seem to be the only two people close to him that don't already know. His mom will probably be okay, she will be a little shocked initially, but she loves and trusts him enough to not be mad. Plus he'll likely have to tell her what's going on in an attempt to keep her away from it.
As for Mina, I'm not sure how she'll react. As time goes on she becomes less and less innocent, and after meeting Hana and Felicia, and developing the friendships with them, it might not shock her as much. Time will tell, I suppose.
If the change in management meant replacing August, Edwin, and Kat with Hana, Felicia, and the MC, so that they could run the club as they see fit, then that might work.
The club could still be about sex, exhibitionism, and similar taboo themes, without focusing on the humiliation, sadism, and threats.
There would likely be a shift in the clientele, but that wouldn't be a bad thing either considering how bad some of them are.
It will be interesting to see how it unfolds.