No, a lot of what people are saying on here is not over the top. It is a story that had a really great premise that is poorly written, poorly executed, poorly ended, and poorly received at the end. It wouldn't even be so bad if the author went through with the revenge instead of wanting to write a generic romantic comedy. This story is also not "fun", nor is it really all that funny. The word you are looking for is TRITE. It's trite and mostly shit.
Just to clarify a bit on my personal beef with this shitstain of a series, subversion of expectations is never a truly bad thing when it is written and executed well. I'm a liiiiitle mad at the shitty cliche ending because that girl was definitely the least liked by me, but it was the execution of how it got to that point that really grinded my gears and made me drop the series until it ended and I hate read the last chapter just to see how much worse it got; it ended up exactly how I predicted it would about 20 chapters into the manga (which was around where I dropped the series). The worst thing about this subversion of expectation is that the beginning has an amazing start and looked to have legs that would carry it to a great ending, but somewhere in the middle it turned into a shit cliche romance comedy (again, something that I actually like, when written well) where everything was predictable and everyone could tell that the artist was trying their damnedest to make the ecchi parts as good as possible, because the story was not the carrying factor. Maybe I just gave it too much credit due to its strong start, so my expectations were higher than normal until I realized I was reading shitty generic romance comedy.
I agree with Fairin: if you are thinking about reading this, I would suggest against it unless you like absolute tripe (there's people on here who like that, can't judge). This is a generic series that breaks no boundaries, which isn't a bad thing, if it was written and executed well, but this story is not. With how things were written throughout, I will assume the author--and some of the reactions from people who know how the author works--the ending was already set in stone, which to me just makes this even worse.
You know things are bad when someone like me (I have rather high general standards when it comes to literary works) will lower my standards to the bare minimum of what is tolerable (I'm entertained), and still get disappointed by the product. But I'm also a person who firmly believes the end has to be as great, or better, than the journey getting to it, because otherwise it's a waste of my goddamn time since I could've invested my limited time into something far, far better.