I just finished reading it, gotta say, for my first fanfic novel its quite good. Although I have some complain about its rushed ending its pretty okay I suppose. I just hoped there would be an after-story on how he develops his relationship with the prospect girls and the future when he retires and takes care of his children and harem.
I'd say 7/10+1 because its my first fanfic and will use it as a standard.