Hey, thanks for the very through reply. I felt less like talking to a brick wall and more figured that you were more active on the Itch page, as I find most devs aren't overtly active on their F95 pages unless they planned to release their game publicly from the start. (Speaking of which, you should submit a ticket if you want to get a Dev title on there!)
TL;DR *is* a valid take to a degree, at least in the terms of "this is a game where you can bonk a shrimp and a shark (or is she a dolphin? It's a bit confusing at times, but I assume shark making dolphin jokes, would it be awkward if you added a Dolphin character later?) and seeing the MC's transportation routine could easily be pretty wordy and overall not matter in the grand scheme of things, but I still feel like these are good grounding moments for the player and can even be used to setup future character/story arcs. One idea that pops into my head now would be perhaps the MC having a laptop/computer/phone that he can check his emails on, and maybe some of these emails are from before the start of the story. How far back would depend, but you could definitely stuff like him getting his job, email exchanges with his boss/co-workers/friends, hell, you could even have exchanges with his parents/grandparents. I'm not exactly sure how the story is going to pan out and whether the lewd conduct will remain solely in the dreamspace or not, but sometime like that could also allow stuff like lewd photo exchanges and the like. Hell, you could do a limited version of GTA and have a few fake websites the MC could browse and get a better idea of the world. The great thing about this is if a player doesn't care, they can just ignore it and be none the wiser.

If you want you can definitely send me the jam release and I'll check it out. Though as you said, I'll probably say something like "oh god!" when I see what it used to be like.

IMO I think the primary thing to focus on gameplay-wise is the way the player "feels". NPCs being a bit jittery can be forgiven by most if the character feels fun to control. My advice would be working on how the primary attack combos with itself and working on a way to naturally combine that with the secondary AOE attack/dash. Since the MC is using a Katana/sword, some kind of beyblade/spin to win dash attack would feel very natural in terms of flow, and definitely some sort of block/parry should be considered. As someone else stated, more obvious tells on what elements do is another great consideration. One of the things I thought when I saw lightning as a option was something like "Huh, I wonder if that will do more damage to these guys because they're aqua/fish-themed?" and I don't think I'd be the only one to think this. So I don't know whether that's a sign that enemies of zones should be more vulnerable to certain elements or not, but it's something to consider.

In terms of art, I think the only negative I could say would be something that a few others have said: The 2D animation looks kind of weird compared to the 3D environment and some scenes might need one or two touch ups, like the way the penis inserts in Shrimpie's scene. One consideration might be mixing it POV shots/variants of H-scenes? This might make it less jarring, as it's easier to "imagine" it as 3D if it's coming from the MC's POV, or at least this is what I think.