Well, I haven't picked through this entire thread yet, and it's more than likely that someone mentioned this already, but if I were pressed to consider the possibility of Aymeric being "evil-ish" I could kind of see it.

The thing is, Nidhogg's actions play into Aymeric's long term goals (peace with Dragons). So, in theory, any evil actions that Nidhogg takes towards Aymeric or his possible allies is to Aymeric's benefit. At the peace summit, for example, when Nidhogg showed up and speared Vidofnir, he kinda sealed the deal. Humans and dragons alike witnessed his barbarism. He made an enemy of both. What better time for humans and dragons to come together against a common foe?

Being a smart man, it's not impossible that Aymeric foresaw such a development and plans to take advantage of the situation. I wouldn't be surprised to find out that he were secretly grateful to Nidhogg for his tremendously stupid actions. A more conniving character might have known that the attack was coming and intentionally allowed it. A downright morally reprehensible character would have orchestrated the whole thing with the intent of greasing the wheels with the dragons.

As for his advances on the Warrior of Light ... If I were being cynical, I would say that there's a lot of political posturing going on between Aymeric and the 3 GC's. First, he has us fight for Ishgard against our own grand companies. Then, at the last minute, he forces us to wear Ishgardian (butt ugly) colours during the melee. It's like he's politely declaring that he is claiming the WoL as his own. Even the other GC leaders took note of it, and despite their politically correct diction, there were a lot of heavy implications (the worst of which being a cold war styled arms race in which we are the arm) ... Again, though, that's looking at things with a pretty cynical eye, and it still doesn't necessarily paint Aymeric as a "bad guy." As of yet, his intentions do seem good ... Though, if he really does plan on taking a hold of our services and creating a united force with the dragons there is room for that cynical eye to stretch a bit to more grand aspirations that aren't necessarily as good as things seem now. I have a feeling that the Garleans will be the major stumbling block to any of that, though.