You did a great job at pointing out the flaws of the ship in canon. I think one of the problems on Angel's side is that in order for the audience to really believe that Angel likes someone, he needs to discover that on his own. Can't remember who said it, but Angel is emotionally 5-years-old and when Lorne keep telling him that he liked Cordelia, he believed it.

However, I find that if I watch S3 and ignore Lorne, Fred, and Groo's comments about Angel and Cordelia, I see a lot more of actual relationship building.