One of my favorite things about Solas is his 'hedge mage' status. I am really looking forward to his perspective and his knowledge which sounds like it will not only be unique but will also challenge many long held beliefs. It also sounds like he does it without the need to yell or crusade but more as a teacher.
I mean, we have been inundated with circle and templar politics. Circle mages are often thought of as repressed freedom fighters but we really haven't heard from mages outside the system. It will be interesting to see their own prejudices and not so nice attitudes come to light. Kind of like the dalish/city elves differences. I know we had Morrigan who was taught by Flemith and talked a little bit but her agenda was more about returning the old gods. Hawke was trained by her father who was also circle trained.
So yes, I suspect the Vivienne/Dorien/Solas dynamic will be interesting. While I have no doubt Solas will be able to hold his own and not need my interference, I hope they aren't overly obnoxious about it or I may be tempted to feed them to the next dragon we find! Or more accurately, I'll just leave them behind at the keep all the time so as not to deal with it 
Yes! I want Solas's perspective on everything. I suppose you could say that Morrigan had this perspective, but mostly she was played up as the Evil Companion, and thus most of her outsider's perspective was lost in the, "JUST LET THAT CHILD STARVE WARDEN."
(No hate: I love Morrigan.) So I'm curious how a more neutral and friendly perspective will help us see Thedas.
And, yes. I hope that a party of Vivienne, Dorian, and Solas is far more palatable than bringing Anders, Merrill, and Fenris. Man that was a rough ride. But it sounds like Dorian is probably going to be friendly, if snarky, and Solas sounds like he can hold his own. Vivienne... eh, she's gonna be mean to everyone, I think. 