Sera question

Tested it myself. It leads to her leaving. So it can't be written off as bad paraphrasing.

So she's a bully. 

She also bullies people who haven't bullied others, so she is indiscriminate thus making it bad. 

I have to admit I thought the pranks were rather infantile and inappropriate no matter how much you want to appear "ordinary" to the people around Skyhold. Still, I went along with it my second run because first run my Inquisitor never even got their approval up high enough to be offered it and my second Inquisitor did feel in the need of some stress release and thought mucking about like a kid might be the way to do it. Then after it was finished, the next time I went to see Cullen had was in the throws of his lyrium withdrawal and it made me feel awful. It almost seemed like her stupid prank had pushed him over the edge (I knew this wasn't the case having already experienced the scene but my PC didn't).

That is the problem with a lot of Inquisition, there is a disconnect between one set of actions and another because they can occur in a random order but in the case of Cullen, whose struggles were on-going, I think the Inquisitor should at least have been able to object to playing pranks on him because it might be bad for him (not just as the commander of the army but as a person). Even if they didn't want to reveal the precise nature of his affliction, you should still have been able to say you felt it was a bad idea in a way that Sera could agree to rather than having to go along with her plan or end up on her bad side once again.

As for the character growth in Trespasser, I think that came about because they were aware of the amount of negative feedback about Sera that had her pegged as a selfish bully and so they went out of their way to correct that impression. Either they had wanted Sera to appear better than she did in the main game and realised they had failed to get the message across, or they did just want to show character growth so more people could like her.

It would have been better if that could have occurred a bit more towards the end of the main game. For example, the business with Lavellan over the Temple of Mythal, where she is utterly insensitive about the whole business. Now at this point you are likely already to know if you have lost your whole clan, so the fact that later in Trespasser she shows sympathy for this is really too late in the day, in my view, for it to redeem her. None of my Lavellans ever pushed the elfy thing on her and made her feel lesser because she didn't want to be a part of it but nevertheless it did mean something to them and I feel she never really respected that, certainly not in the main game. She never seemed to get that she was just as bad in her own way as the "elfy" people she criticised.

In order to be friends with Sera I did have to overlook things that really did not sit well with me and it was annoying that otherwise I was being labelled as not interested in supporting ordinary people just because she was their apparent spokesperson. My PCs constantly want to champion the ordinary people, hate being forced to play the Game which could be to their detriment or lie to them about the truth of the Herald but that is never acknowledged by anyone. The only person who is meant to be a champion of the "little" people is Sera and to be honest she really isn't. That is the image she likes to foster but the reality is the Red Jennies serve nobody but themselves.

Vivienne's character was the least completed. They ran out of time for everything they intended with her.

Isn't this the same problem the homophobes have with gay flirt options? IF you don't want to use a dialogue option, don't select it. Why is its mere presence a problem?

Yes, but once people choose not to flirt with the same-sex romance partner, does the option come up again?  Like Liam in MEA, it's pretty clear once the flirt attempt fails that nothing will come of it and there is nothing shown from that point on.  In theory, I agree with what you're saying.  In practice, I wondering why BioWare seems so intent on me booting Sera.

Honestly, at some point there should have been an option to remove Solas as well. He also kills people right in front of you (three if fact) if you don't stop him and afterwards he acts like a condescending racist when you talk to him.

Really after Haven there should have been a way to remove any of the companions.

True, but afterwards I really don't think he adds much besides learning about where Red Lyrium came from.