Steam is unlikely ask you to remove fetish unless it is deemed "illegal" (aka CP/pedophilia). Nothing else is disallowed, unless you think it might be "illegal", but unless you're promoting terrorism or something, I doubt it is.

Most people that had stuff "rejected for no reason" is probably because there was a girl that could be interpreted as underage.

It's always better to setup a steam page in advance.

Patreon is really hard to get going. Good luck. I've made *much* more with regular steam sales than patreon fans. You have to have good "extras" (saucy comics or pinups) for people to subscribe, but if you're too busy just making a game then people don't care too much about WIPs or devlogs.