I’m not an expert on what automation options they might offer, but I know Aurora Store will essentially just pass through anything you do on the Play Store since it’s just a frontend, and for F-Droid you can host a repo where you place any updated APK to automatically make it available to anyone linked to your repo.
I know alternative payment options are probably a nightmare to properly set up and integrate, so it may not be worth the increased cut of revenue you’d get, but I’m really glad you’re considering it!
I look forward to trying the game when it comes out :)