If you say that we don't know if he tried to find an alternative way to open it, don't claim that he didn't try to find an alternative to open it
In fact, how would he know that he was too weak to unlock it, if he didn't try it?
Also, I never claimed that Solas acted out of complete altruism - what I'm saying is that choosing to eliminate a supremacist group and their leader hell-bent on conquering the world is still a point FOR Solas, rather than against him, because of all groups or people he may have been able to chose to eliminate he actually picked one that actually was a genuine threat to pretty much everyone. You don't have to act completely altruistically to still make decisions that are beneficial rather than harmful to others, which seems to be Solas's chosen modus operandi.
Also - how do you know he didn't wait for his powers to go back? Where do you extrapolate that knowledge from? How do you know that he's not acting not out of impatience, but necessity, because something is coming and he's running out of time? I mean, the dude has spent THOUSANDS of years in the Fade, quiet as a mouse - you think he wouldn't wait a couple more centuries if he deemed it necessary?
Based on what we can see in the game I'm pretty sure there's either something coming, or there's a specific time frame (I predict that Solas needs some special celestial event for Things To Happen) that Solas is waiting for OR is himself running out of time. Among some other hints he did state to Varric, when the dwarf defended the Wardens, that for all the bad they did they did indeed buy "us" (as in, he counts himself in) some time, like there some sort of gruesome fate that awaits Thedas that is unrelated to his own plans. And given that we see eldritch horrors coming from each dark hole now and the world is constantly threatened by the Blight (which Solas is terrified of, btw) it's not that hard to come into a conclusion that we've not seen the worst that can befall on Thedas yet.
I meant that he had no one else to give the Orb to, Corpyheus was the only viable alternatice since he didn't want to wait for his powers to come back. Again, something good came out of the whole debale but, IMHO, it wasn't really the desire to rid the world of a maniac that motivated Solas to give Cory the orb. It was desperation and, also, an uncaring attitude towards the damage Corypheus could have caused with it. Hell, he doesn't even show regret about all the people that were killed at the Conclave(and he knew the orb would cause such an explotion so, again, since he gave such a tool to a maniac, it's implied that he didn't much care about other innocent people who would die because of it), he just regrets that Cory delayed his plans.
Because he literally says to Flemeth "After my sleep(from Trespasser we know he woke up 1 year before Inquisition) i was too weak to open the orb". Also, since we don't exactly know how uthenera works but what we do know (from Solas hismelf) that to rivist the fade history of a place it's necessary to be physically in that place, it's more than likely he did all his exploring in the Fade after he woke up, not before
About Solas "the hypothetical savior"..... yeah, i disagree. There was the mage/templar war, but apart from that there is no evidence something "bad" was going to happen, or something worse than the norm anyway. I think he's disgusted by the Blights for the same reason Cory is disgusted by the Blights, they are horrible things that weren't there in their times (well, possibly they were in Cory's times)
Plus, honestly, i think "ancient evil coming back and the bad guy is the good guy" would just be detrimental to his character. He's fascinating because of the way he is, a layer of secret niceness would just make him less complex
Wut? Okay, how is deeming people as petty and self-centered somehow a mark of someone who condemns or doesn't care about people? 
Leliana does it so too (Inky can even point out that she has hardly any faith in Thedosians, after she calls mast people small-minded and so on). So is Cassandra in fact in banter with Solas himself! (Solas: "People can be trying, mankind most of all." Cassandra: "That... is an excellent point."). Dorian keeps going on and on how bad the Tevenes are, yet he's in fact deeply caring and patriotic. Even Varric, a people's person, oftentimes doesn't have high opinion on them.
Seriously, saying that someone deems most population as petty and self-centered is hardly a hallmark of "not caring". I myself oftentimes bemoan the fact that large swathes of population are small-minded and petty - hardly makes an uncaring person; in fact I bemoan that fact precisely *because* I care.
But I digress... I've already pointed out numerous times that there's ample evidence i the game that shows that Solas does indeed care - the banters, the approvals, the actions. I'd also like to point out that Solas saves Inky and South even if Inquisitor never really became a catalyst for Solas' to change.
My point was that one of the reasons he risked giving Cory the orb is that he found most(/all) people to be lesser than what he remembered. As is aid, he knew the unlocking of the orb would cause an explotion and since he did give it to a maniac, well, he either didn't care about the risk of Cory killing innocent people while unlocking it OR he didn't really care about thinking his whole pan through. Either way, he knowingly risked people's lives because he didn't care
There's a variety of reasons for him to do it, one of the main one is in fact laid out most clearly on enemy route - "your death would cause more senseless chaos. More bloodshed. It is unnecessary."
So he saves disliked Inky and stops the Qun specifically to prevent unnecessary suffering. As for befriended or romanced Inky, he obviously has personal reasons to save them, but if a friend!Inky chooses redemption route, they clearly state they they will prove Solas that the world doesn't have to be destroyed. Solas's response? "I will treasure the chance to be wrong again, my friend".
So, yep. He specifically saves them to give the world a real fighting chance and appears prepared that he may indeed be stopped.
Honestly, this whole thing describes why i find him so dislikable and just why his attitude kind of ticks me off. He plays god with people's lives, and claims to despise gods, judges everyone based on his own messed up morals, and yet based on his actions he's the one who should be judged, wants (and probably will) to kill lots and lots of people, and at the same time he somehow wants to The Inquisitor to prove him wrong (like, yeah, just killed a person but now please prove i did wrong in doing so).
Truth be told, i dislike and feel sorry for Loghain because he, at least, had no idea of just how much he was wrong and how badly he was messing up. At least he was fighting for something real. Solas fights for something that is no longer there and, as he says, would sacrifice Thedas for the off-chance to get it back. Tragic in a way, since he's becoming just like the Evanuris of old, but it's so despicable to my eyes