*snip*
To sum up, I think he might be looking for a less destructive way of restoring elves with a conscious connection to the Fade, but if he can't find one, he'll tear down the Veil anyway, if he can.
Just trying to figure out some of the other stuff he says that might refute the possibility that he is looking for a less destructive way to restore Elves with a conscious connection to the Fade, if he can...
If a romanced Inquisitor chooses the "I agree with your goal" dialogue option, this is what follows:
Lavellan: "Let me help you, Solas."
Solas: "I cannot do that to you, Vhenan."
Lavellan: "But you would do it to yourself? I cannot bear to think of you alone."
Solas: "I walk the din'anshiral. There is only death on this journey. I would not have you see what I become. It is my fight. You should be more concerned about the Inquisition... (etc.)"
I'm not sure if he means death for himself or death for others. When you come across the Qunari who died of terror in the shattered library, I am not sure if the Librarians killed them or if it was Solas in his Dread Wolf form. It seems likely that it was the Librarians, since they look like spirit fear demons, but... they only show up in the Courtyard of the shattered library when we meet them. I'm not sure if we should assume that they were moving around before Inquisitor & Co. run into them. If there's a risk of Lavellan dying just seeing him as the Dread Wolf, of course he wouldn't want her to see what he becomes. Also, pride demon/wolf hybrid = probably not conducive to warm, fuzzy feelings like love. Then again, he may literally be saying that whatever he's planning is going to be the end of him - ancient immortal elves can be killed, as evidenced by Mythal. Would he be so fatalistic if he thought there was a less destructive/guilt-inducing way to achieve his goal? I think we don't have enough information to understand what the "dinan'shiral" might actually mean to an ancient elf. This might have to wait until DA4 to be explained. :/
Edited to add: Since Pride demons have been established by DA lore to be one of the most powerful demons, is Solas consciously choosing to become more prideful/less wise for the power, because he needs it in order to accomplish his goals, since he lost his orb? Could that be what the "dinan'shiral" is to an ancient elf - giving in to the darker emotions? (Or is that too Star Wars-y?
)
Another edit: Living Mythal seems to have been more Justice-oriented; her spirit strikes me as very Vengeance-oriented. So maybe 'dead' ancient elves are ones that have turned/been turned to the darker end of the spiritual spectrum. I don't know. I wish I didn't have to wait several years to find out! 