Oh Alistair...he was my first video game love. Sure..there were others I found attractive ..but Alistair captured my heart. I'm actually playing DAO again right now (yay I got the disc working again), trying to do a Zevran romance since I've only playing through it once with him..it's always been so hard to resist Alistair.
But now...it's like..meh... Alistair is still a cutie...but he doesn't even come close to Solas.
Alistair really appealed to me when DA:O first came out. I was fairly young and thought he was funny and cute and all that. He's my canon warden's romantic interest for that very reason. These days I find him endearing enough, but not much more than that. He certainly can't even nearly compete with the level of uninhibited fangirling that Solas brings out in me... unless it's Inquisition Alistair, for some weird reason. Part of it might be DA:O nostalgia doing stuff to my head, but I seriously find him so attractive it's almost painful. He's SO PRETTY. And it's seriously all about his appearance, because his personality seems more or less identical to his DA:O incarnation. I'm a terrible, shallow person. 
With Solas, it's sort of been the other way around. Didn't find him overly good looking at first, but his personality discreetly hooked me within ten minutes of starting the game, and just kept reeling me in bit by bit almost without me even noticing it, because that is one seductive egg. His voice was just amazing, and I found myself going through all of his dialogue in Haven before I had even said hello to most of the other characters. Then he was all smooth and suave and intelligent and interesting. Then there was fade tongue, and I was lost. Now I find his appearance ridiculously attractive, and I kind of keep wondering why I didn't see it immediately. 