my complaint is that we didn't really get to see much of what he accomplished before or how hard he worked for it. So it doesn't have the feeling of the mc getting the big payoff they deserve. It's like the author just assumes we care about him and want him to get whatever joy or catharsis he wants. I mean, just saw this weeks episode of Kimetsu no Yaiba and that definitely made me cheer at his success. The training, plus all that happened before, made it feel earned, like everything was coherent and clear and never random or the result of something offscreen. For this so far, everything either is or might as well be random. If you don't show the mc working to get what they want, than there isn't any difference for the reader between them and some bratty heir buying things with their parents money.
Also, the fact that the blond girl is bigger on the cover than mega(ne-)boobs does not bode well.