On hugging -yes. I wanted to hug cassandra, cullen, Dorian, Cole, Sera, Solas - though I think if you hugged Solas he would just breakdown and cry or something. Dude just wants for affection so hard. I wanted to HUG EVERYBODY. You get to hug Varric but only if you kill his friend.
Oh god. Yeah, I really got that feeling during some scenes. Especially since touch seems to trigger him to break through that stoic calm of his. Before the Fade Kiss, for example. Or during the balcony scene. And in the final scene, when Lavellan reaches out, he backs away from her touch so quickly.
The scene that makes me want to hug him the most, though, is this one.
I took the dialogue option once just to see what would happen (before reloading as fast as I could). And...oh goddamnit, why won't the stupid game let me hug him? 
And yet, all that aside, I just couldn't take it seriously. ;_; I'd headcannoned that after the ball is when Ilaria and Solas doink for the first time, but I'm even laughing thinking about it now.
I headcanon the same thing. He's just so...uninhibited at the ball. It's wonderful. I did Halamshiral right after Cole's personal quest (where I made him more human) and Adamant. And right before that was Solas's personal quest and the balcony scene. So all I'd seen for a while was Sad Solas, or Solas being super cagey and weird. I thought he'd be grumpy at me for bringing him to be ball, too, but nope. The big nerd was having the time of his life. And drinking all the wine while I was running around doing all the work (the bastard). I just about died when I asked him if he had any interest in dancing and he was all, "A great deal~" And yes, that line totally had the vocal version of a tilde at the end.
I don't even think it's the fact that he's tipsy that makes him so wonderful at the ball. I mean, that's a part of it. But the tipsiness just makes him less stiff. The real reason why I love Solas at the ball is that he's happy. For once in the entire game he's going, "f*ck it, I'm going to have a good time". And it really shows.