Lewdpatcher hasn't been updated to the current game, it's unlikely to be updated as the game's been updated. If you use lewdpatcher, it's only work for the version it is listed for, not the full season 1. You'll end up with errors everywhere.
I think the infamous patch is someone else's version of the lewdpatcher, just the script changes they think make sense, like lewdpatch was, and the uncut version is a fan made one restoring cinematics that were cut because of licensing, scenes that were changed or shortened etc.
If you want to see the historical versions, the uncut mod is the only thing you need. If you just want something equivalent to lewdpatcher (ie keep all the official renders the same), the infamous mod is all you need. If you want to carry your save from season 1 to season 2, mods might cause that to fail. Season 1 unpatched is the only supported save that will import into season 2... Ocean won't guarantee the game works with any third party mod.
That is what I'd thought but my understanding was the third game idea with the female protagonist will be set inbetween WiaB and SG. Ayua would have to be in a fourth game then, which is far too distant for me to even register as a thought process. I'm far mor interested in the Ayua in that render to wait for the planned fourth game.
There is no problem with siblings being LI's, as long as they are solo paths ie. you can choose one of them, and only one, no throuple possible, door a or door b, choice swings shut behind you.
Edit: just noticed - does Ayua call that duck Sasha?