You know why I find it strange? because he seem to became interested in doing something for the elves only after the Temple. Before, he seem to be only angry to the Dalish and pity the City Elves. He doesn't seem to be in any way interested in helping any of them. It seem like he tried to talk to the Dalish, and when he tryed to tell them something, they just send him away, maybe attached, and surely insulted him.
He doesn't like them, and doesn't want to help them. Actually, I think he doesn't really have to help them. Somehow, the situation as sad and bas as it is, is quite stable for both City and Dalish after Cory is gone.
He became interested in the world only after stayng in the Inquisition for a while. So I think whatever he want/have to do is something he have decided to act about only after the Temple, and not before.
No, he wanted to unlock his orb because he wanted to do...something to help. This stuff weighs upon his mind long before the temple. Solas' banter with Cole is one place where we get hints of the inner conflict Solas carries.
Cole: You don't need to envy me, Solas. You can find happiness in your own way.
Solas: I apologize for disturbing you, Cole. I am not a spirit, and sometimes it is hard to remember such simple truths.
Cole: They are not gone so long as you remember them.
Solas: I know.
Cole: But you could let them go.
Solas: I know that as well.
Cole: You didn't do it to be right. You did it to save them.
Inquisitor: Solas, what is Cole talking about?
Solas: A mistake. One of many made by a much younger elf who was certain he knew everything.
Cole: You weren't wrong, though.
Solas: Thank you, Cole.
Though one can argue that Solas' time with the Inquisition personalizes the people of Thedas, and has made him question certain assumptions he had made based on limited knowledge or judgments. They're more 'real' to him individually and he has learned something.
Whether people are still pawns on a chess board after that, well, we'll see what he actually does.
But all of this weighed upon Solas from the beginning, which was why he tried to get his power back. If he had gotten his power back first, I wonder what might have happened without those experiences he had with The Inquisition....given his positions that he has learned from by game's end.