That's how it works?
Solas fans are permitted to devise suppositions not based on evidences in game (that's exactly what headcanons means) and call the jury out for that but the others are not allowed to do the same thing otherwise they are called on their own assumptions about Solas?
I'm still trying to figure out what exactly is your problem with my opinion. My opinion that maybe our decision later on about Solas... it may be a harder, more interesting decision than the decision we're faced with right now.
All I said was, according to these these things, they may be clues of something later on. Or they may not.
The fact is, we don't have all the facts. That's not head canon, that's just fact. Does that automatically mean that Solas is going to be up to something that turns out to be noble and good? Nope.
Does that mean you're not entitled to your own opinion? Nope.
Does that mean our decision later on about what Solas is up to, is maybe going to be a harder decision that it seems to be right now? Maybe.
What the heck is wrong with me saying maybe? Golly geee wiiiizzzzzzz.
Are you on an anti-maybe committee? Does the word maybe dredge up personal tragedy? Are you King Maybe and must kill all the pretender maybe's that are threatening your Maybe Throne?
It's okay if we're in disagreement. The world will continue to spin around the sun. It will still spin on its axis. Seasons will pass. Flowers will bloom. Game of Thrones will continue with its awesome. Cool Dragon Age games will be made. Mysteries will be solved. White chocolate will continue to be tastier than regular chocolate.
Go look up head canon. Canon is facts. I said certain things may be clues. Sandal's prophecy isn't head canon. Nor is Flemeth's prophecy with Hawke. At the end of Trespasser, Solas doesn't want to kill lots of people. He feels he has to kill lots of people. Restoration of the elves is definitely a motivating factor. But is it the only motivating factor? He won't tell us about everything that's involved. So, maybe it's not the only motivating factor. Solas has had to make hard decisions before that involved saving the world. That's possibly a clue.
*no maybe's were harmed in the making of this post. Head canon's felt left out, but were compensated with Tyrion Lannister action figures.