I'll try to take a stab at this from the perspective of a futa enthusiast. I like the groundwork in this game. The setting, the characters, the art, and the ideas are all in good places to make an excellent game in my opinion. Where people have some problems (myself included on occasion) is in some of the execution.
I think the story feels a bit rushed and the dialogue tends to read unnaturally at times which breaks immersion. I'm not sure if English is a second language to the dev or not but regardless writing convincing engaging dialogue is difficult and is exacerbated in this game because the story is told in dialogue from the MC's point of view. I think getting someone to edit the dialogue would go a long way in fixing that.
While I appreciate the location design and I'm happy that you have characters who look significantly different in body type and not just a range of palette swapped thiccc bodied MILFs or women with all exaggerated curves and huge breasts. That being said movement is tedious. I can get around the shower if you're covered in sexual fluids but clicking through three-five locations screens to go back just to change clothes to go outside the ship or to the club feels like unnecessary effort and having to remember the five or more areas to click to get to another part of the ship for your quest is also irritating when I'm just trying to get to the next part of the storyline.
I agree that the futa doesn't feel very optional when the MC clearly states he does not want to engage in sex and ends up getting forced into it only to not care that much about the sexual assault 10-15 min later. I was also hoping that in the VR video gaming scene when Lana takes her dick out the MC would just tell her that's a horribly porntastic way to get a BJ and he's not falling for it but alas it was not so. I think any scene should have an opt out option in adult games for people who don't like certain fetishes or just for player choice. If you only want to engage with one or two characters on the ship that's fine.
That brings me to our largest gripe. The MC. My guess (and feel free to correct me if I'm wrong) is that the goal is to portray the MC as a man from our world suddenly thrust into a strange futuristic one and forced to find his feet quickly to right the wrongs of his body's previous possessor. In some ways his reactions make a lot of sense. I think most of us would have some degree of confusion or apprehension to discover not only aliens but aliens looking exactly like human females just with large penises instead. Those apprehensive feelings would likely become exponentially increased had those aliens then become very sexually forward before you could even decide how you feel about them. An outburst or two is warranted in this case.
The problem is that the MC feels like he doesn't quite gel into the real world. He comes in action and behavior as a sort of incel turned wannabe chad. I think it's highlighted well in a few scenes. First is when we see Zara and Ashalanora walking and the MC wants to talk to Zara. He then follows them to the spa with the ladies sauna in it. He eavesdrops on their conversation (which is very normal for an adult game) but as soon as they mention that he might be gay his inner alpha male roars to the front and he storms the womens' locker room to proclaim his staunch heterosexuality as any mention of faggotry is obvious an intolerable stain on the reputation of any good alpha chad. It ends up feeling like a creepy guy listening to the girls talking as they change and then barging into what is very obviously a change room to awkwardly say "hey I'm not gay" as if he expected them to just brush it off and say "OMG I'm so glad you could clear that up! lets do sex now." when its actually a very unnatural social interaction where you as the MC are forced to be in all of the wrong. The other scene that struck me was when Zara insists on a blowjob and mentions that polyamory is accepted among futaliens that the MC immediately forgets the impending blowjob that he's ardently arguing against giving (again because of his need for alpha-chad-maleness) and daydreams about having a harem quickly until Zara basically cockslaps him in the face.
I get the sense that the dev is trying and I appreciate that and the effort that has gone into this game. I really do want to see it succeed and I believe that I can do so. I do also however, believe that its being held back by writing and an MC that feels to me like he's one step away from the obviously a fuck boy Chad character. He seems the type that if he was rejected he might hack a bot into drugging a chick to get back at her. He certainly didn't try to stop her when he thought she might be drugged, and the sudden knee jerk reactions and random thought tangents and lack of real choice throw me off when I'm trying to get into the story but all of those things can still be fixed, so I hope the dev can go back and make some change since like I mentioned I really like the idea of this game and I definitely want to see it succeed.
You basically touched on a lot of things I could mention, but I don't really feel like talking about all that since I have no idea how seriously the dev will take feedback (or even read it). The MC just has a lot of flaws that make him truly unlikable, and now that you mention it, he really is like an incel and it hits right on the nose what makes him really annoying to follow/play as. I don't even *want* to help this guy, like from the very first scene his decisions were making him super creepy. I gave it a pass at first but the more I played the less I was liking him. Some of his reactions to the girls (I didn't get as far as the aliens, so can't talk on that part), is just straight up bigotry. Honestly, a way to preserve his reticence and yet make him likable is not to outright bash/hate/dislike/claim disgust, but like be confused like. He could've been so much better.
Lana as example since she's as far as I got: He thought she was really beautiful and admired her breasts (again, creepy, but whatever, pass here because porn game). Then finds out she has a dick, and he does 180 flip in how he feels about her. Instead, he could've been confused or conflicted. It didn't have to be love/hate, it could've been "damn she's really hot...but she has a dick...but she's into video games and hot...argh!" <---something like realizing it might not be how he wants, but then after talking to dad or overhearing conversation with the mom, he could've become more curious or I dunno. I didn't get to the VR part you mentioned, when he just made her cry and run away I am just done.
I'll wait and see if the dev even takes feedback or might do something to change MC in the future, if so I might come support this game, the concept and art is really good. Regardless though, I don't feel like playing this anymore until it gets an overhaul.