So yeah, my Lavellan would go all the way for him. I'm actually playing a really bratty warrior, who's pretty much of a brute and dutiful to the bone. She's the one to get the job done, but she jumps to conclusions fast and doesn't take kindly to anyone who seems weird to her upon meeting. As a result, it's quite interesting to give her Solas as a Love Interest, since she's mostly brawls instead of brains. I'm headcanoning her as an elf that was supposed to be the Keeper in the future, but ended up as a normal warrior instead because of her lack of magical talents, so she's pretty smart deep down but just prefers to be an a** sometimes. Because of her personality, I'm hoping for a way to pretty much slap the questions out of Solas - with words, but still. I want options for Lavellan to be deeply shocked and angry. I really want to be able to make her cry her heart out, though. She'd get back together with Solas, yea. Probably. She's pretty broken anyway, so she'd cling to every little comfort that she could, even if it came in the form of an elven god who left her years ago.
One thing that I'm really interested in are conversations about the vallaslin, because she kept hers - not because of her heritage, but because it is a part of who she is. She's not willing to change for Solas, so if he would propose something like it (even though I doubt he would) she'd dump his sorry egghead. She wouldn't be willing to go into uthenera for him to 'fix everything', for example. It's either nothing or him and her 100% even in misery, because misery loves company.
(So much infodump, I'm sorry~)