Having just finished a play through of this game, I gotta say I liked it. I have only gotten ending 4 currently, but i do plan to get the others later.
Though my one criticism would be the writing felt a little lacking. Like it's not bad, but the relationship between Alya and Un felt a bit rushed, parts of the story could definitely be more fleshed out, and I wish the side characters were more developed. Like I woulda liked to see more of the teachers besides Willz and some of the other students. Definitely more of Alya's dad. But I do think you have a good base here.
If you ever get the chance to polish things up, the whole thing of new art, a non-default ui, drawn backgrounds, a original soundtrack, a more fleshed out story, and maybe even an animation or 2 (i'd love to see an animation of Alya and Un dancing in the competition), I'd take it. Cuz I could totally see this being sold on Steam.