Don't get me wrong, a Pokemon harem (gotta catch them all) is a thing I usually enjoy, too. However, sometimes I feel like a certain girl would make no sense to me ("No, I am not forgiving what you did"), sometimes I think the relation is too stretched storywise, sometimes I just don't like a character for whatever subjective reason. Having to decide against a girl you are interested in is one thing, but in a "full harem" game my decision has already been made for me, and it has been made wrongly, which makes continuing their scenes annoying. More so if you are given the choice by the game and it is just ignored. Imagine being asked "What do you like to eat?" - "Pizza" - "Okay, steamed zucchini it is."
Here I don't mind Bethnessa (hey - you're from a famous family, you get a celebrity couple name) too much but if they weren't there I wouldn't miss them and it would make the core group and its story more concise admittedly.