To all those people hating on Mycroft for whatever reason it is, you are basically doing what the fans of Sherlock who hate Elementary are doing; voicing your hate for something you know little to nothing about just because it doesn’t go with what you want.
I don’t like the fact that Mycroft and Joan were together either, and the fact that he wants to continue a relationship with her does make me a little uneasy. But some of us in the fandom actually might like him as a character, or are excited to see what challenges or danger his character will bring to the show.
If you’re expecting Sherlock and Joan’s partnership to be smooth sailing all the way to reichenbach, then you are watching the wrong show. To me, there needs to be obstacles standing in their way, if not to give the show some excitement, but also to make their partnership and friendship stronger.
So please stop verbally abusing a character you don’t understand. We don’t know what his end game is yet, but we will find out together.
Just my two cents. I don’t expect the Sherlock/Joan relationship to be smooth sailing, and I’m not particularly fond of Mycroft, but that’s just me. I can’t speak for anyone else. A little of my annoyance (or most of it) is due to him being favoured over Watson every time he’s in the picture. Doherty talks about the relationship between M and W, and it’s all about how it affects the Holmes brothers, and barely mentions Watson, who’s the other half of that relationship. It’s the way Doherty approaches the situation with his favoritism that unfortunately causes the dislike to spill over.