It was very story-driven indeed, but as for the great story...no. It sacrificed too much of its worldbuilding in order to hammer its themes home, and sacrificed too much consistency and common sense for drama. They attempted a great story, but it proved to be far beyond their competence. Certain parts play as if the writers of a soap opera attempted to write an SF story. Maybe the limited word budget was partly to blame for that, since I know that at least one of them can write better than his parts in ME3 turned out to be, but a great story it was not. It was a story that could've been great.
DXHR had a good compromise. You could see the first sentence of what you would say if you hovered over the selection box. That worked reasonably well, and I don't understand Bioware's adamant refusal to consider it.
I think it was one of the best stories I've seen in a video game, especially one with any kind of choice (more freedom = harder to tell a story) of character. I like the DA games better (think DA2 is a better story - not a better game - than DAO), but I think ME3 was the best story of the 3 MEs and a better story than most games have. I don't know how it sacrificed "world-building" - it was my introduction to the world, and it felt quite immersive, and playing it later, it didn't seem any less consistent in world. It was very big on theme, but I think the best stories are. So that may be a matter of taste. I'm not saying it could be better. Most game stories could be better. But I still enjoy the story of ME3 quite a bit. I've replayed it several times.
I can't imagine how to make a game both a good RPG and fun to watch. Everything that makes a game fun to watch gets in the way of roleplaying.
That a game is fun to watch is a bad sign, in my opinion.
Most of the RPGs where I feel most empowered to RP (feel like I can empathize with, inhabit, and put myself in the role) are entertaining to watch.
Maybe... Different people roleplay differently. I like choices, but I am not interested in going against the grain of a game, like some people seem to be. I like Skyrim but it loses my interest a lot because it doesn't really give me a sense of story and character and it lets me do everything, which feels unrealistic to me. Limits are powerful story tools. I'd rather be given something to inhabit and roleplay with that point of view with some choices but also some parameters that are reactive. To me, the ME and DA series both live up to this well. I become Shepard, and she's mine, but she's also her own. I enjoy that. But to each their own. To me roleplay is less "do what you want" and more "inhabit that role and make choices based upon what your given."
I think ME3 could have done more with the choices - made them matter more to the ending - but I understood why it didn't. I'm ultimately fine with it, and I enjoy its cinematic nature.