Yes I agree with you on the point that some places reach an "epic scale", the Architecture of some places is really great.
Though I have to disagree with you about the single most greatest building, because in my opinion the greatest landscape-design and especially the greatest Architecture, belongs to Guild Wars. I have never experienced the "blown away" effect you've described so many times in a single game (when you count the Standallone-AddOns as one game), as I had in Guild Wars.

By the way, it would be really much better if there was an option to disable the HUD. It really takes some atmosphere from the screenshots.

He, who does not fear his own sword, is not worthy to hold it.