I can't guarantee giving a top 5 since I read each novel in a different mood and moment. But I'll try, I just hope you don't blame me if you don't like them. I will give you novels of quite different styles so that you can choose your fav.
The Perfect Run - I read this one recently and I liked it, the protagonist is crazy in the head and that's what makes it great.
The Second Coming of Gluttony - This is one of the first ones I read and maybe that influences my opinion but I think the world and the story are very good. Romance is harem, but it is not the main point of the story, it is your choice.
A Stay-at-home Dad’s Restaurant In An Alternate World - I especially like this because the Slice of Life, the MC's relationship with his daughter is beautiful. It heals your heart. The end is meh. It says it's a harem, but it's not. Although he is surrounded by women but only the wife has a special relationship.
As I said before, this one too.
I'm out of space, ask me if you want more.
