Perhaps such a dislike to the request to allow the possibility of romance with Vaylin due to the fact that some players see it as just a maniacal killer, crazy, but as I recall KotFE, Arcann was also not nice and nobody talked about the possibility of a romance with him, but as soon as it became clear that he could become a companion in KotET that he has changed due to the possibility of redemption, so suddenly interest in the question of romance has grown. Personally, I think that the game will not suffer if Vaylin will make it possible for a relationship, but only if it also will have the opportunity of redemption. This is what first you need to achieve, and then a romance thinking "the taste and color-no friend" as they say.
Give Vaylin chance