I enjoyed the story, but that's all it was to me, a story. Not going to lie, I'm really not too into VN's. I prefer Action / Adventure, like say Evenicle. Combat + Sexy Times. I noticed a few times as well, when Seren was referred to as Sybil not sure if I missed something there or not, I get it when he calls Seren by his old consort's name.
Anyway, I think you've got the writing mostly down, just need more lewds, and maybe more choices. Of course more choices is more work / money spent doing branching, so it's a balancing act.
You might also want to look at your Patreon tier rewards. Most games, (and yes that is a broad statement), release a public version anywhere from 1 to 2 weeks after the Patreon version, yes some are longer, but due to sites like this, non-supporters rarely have to wait more then a week for an update to hit public.
I really don't see much difference between a 1 and 2 dollar tier, your $5 will be your backbone supporters with a small to medium amount of $10 pledges. There really is no need for a walk-through as the game stands now, so a walk-through as a tier reward is basically meaningless. (Yes, my opinion, and we all know what opinions are worth, but still.)
In any case, best of luck with your new venture, and perhaps someday you can come back and finish this game/story.