First let me say, I don't want to pile on and ultimately think you should make the game you want to make. I am just a harem fan who is disappointed by the vast majority of harem games out there so I'm going to use this opportunity to vent a little because one particular point you keep making struck a chord with me.
You keep citing Catherine and Malaena as your examples of two characters whose personalities wouldn't fit a harem game. But those are the exact two characters who in the 0.1 demo led me to believe this might be an actual good harem game.
The thing about the harem fantasy that most western devs don't seem to get is that it's not just about the MC sticking his dick into literally everything, but it is about making as many characters as possible happy; and not just with the MC but with each other.
The reason Catherine and Malaena led me to believe that is what was going to happen was that they are the two characters (besides Stacy) who most express their enthusiasm for their shipmates as not just work partners but a family. They talk about how much they care about the others and how they have helped each other. This, to me, is one of the most straightforward paths into the harem fantasy there is.
(This is a porn game, 99% of your audience wouldn't bat an eye at all of the female characters being bisexual.)
Obviously this doesn't extend to all characters. I would absolutely not expect the Red Queen, for example, to join a harem as that doesn't suit her personality at all. She doesn't express interest in any of the characters as anything other than pawns. Likely none of the side/non-crew characters would be suitable.
But that's not the case for Catherine and Malaena.
But it seems like western devs' view romance as solely for monogamy and polyamory is just about fucking and that's a consistent disappoint for me across most of the games I've played on this site.
Again, I wish you success in making the game you want to make and hope you have success with it. Just venting.
(I will admit that, yes, I was considering joining the Patreon before the harem was ruled out.)