Yeah, they're having an Omnibus vs Unified structure discussion on AnimeSuki right now. For me though I don't see much of a difference. Sure, the omnibus format makes the romance stories feel rushed in comparison to the unified stucture. That's to be expected. That's something I don't like about it. On the other hand, some of my favorite ren'ai game story adaptions have been very short - one episode each in Suika and 3 episodes total/roughly one episode per character in ONE ~ True Stories.
So really when it comes down to it, it's not so much what format the stories are told, it's how good the original stories were to begin with. A mediocre story is going to be mediocre regardless of what format it is. It can be improved somewhat by the anime producers, but it'll never become very good unless they alter the screenplay.
In terms of getting more complete stories though I'm all for omnibus formats. They can turn out to be the most similar to how the games originally went.
And yeah, that SEX at the end of the fourth episode was not necessary. I don't see the point in putting that into a TV adaption. In fact, for this type of story it wasn't needed at all.
I like Amagami SS, but the stories feel too shallow to me. I guess I prefer more drama in my romances. I don't want as much drama as "Kimi no Iru Machi" manga (after chapters 70-75 or so) though because that would just annoy me to no end. At that point I stop caring for the characters and the story feels like a big depressing drag.
EDIT:
Too bad...I got spoiled on how Ore no Imouto episode 5 is going to go.
