It's amazing that the game is such a success, even though it fails in every individual category.
The story is just so simplistic. Yes, they have made up a huge background (which is all told in dialogues or the codex), but as far as the game play goes, there's no real drama. Situations feel made up and those supposedly difficult moral decisions are worthy of a fairy tale for 5 year olds. And they largely have no effect. The plot is pretty rigid, it might as well be a book. And if it was a book it would suuuuck, because it's so shallow. Yes, I know there are different endings, and I haven't finished the game, but I'm talking about the bulk of the time spent with the game here.
The action is acceptable, but it's nothing compared to proper FPS games. Your team is mostly meaningless, you can get through the whole game with one pistol and nobody on backup. Just hide - wait - shoot - repeat. Yes, the team makes it faster, but it never feels necessary.
RPG? Please... On this account it fails the most. Leveling system is there just to occupy more of your time, weapon upgrades are tedious and unrewarding. They even got rid of ME1's side quests. Yes, they were all created by a copy-paste, but maybe improving instead of removing would be a better solution? Instead they added the resource harvesting, which is fun for about 2 planets. After that you need to have a major case of OCD to be bothered with them.
They tried to make team members' stories a bit deeper, and they succeeded to some extend. But it still frustrates me that everything has to conform with one game mechanic. You find a team member. He occupies a certain place on the ship. He can teach you to get certain upgrades. After a while he presents you with a personal problem and upon completing said quest you gain his loyalty (and oh so important alt costume). Repeat ten times. This same pattern makes me dissociated from the characters, they feel unreal, they feel like a checklist. I love the illusive man thought, in addition to having a badass appearance and voice, his missions are always surprising and original, which is what this game misses so much.
And then the universe! The whole known universe at your disposal, sounds EPIC! Then you realize there are only a handful of planets you can visit. And upon visiting them you're presented with a 4 room location (but honestly, it's a huge colony! There rest is just irrelevant to the story so stay in those 4 rooms). Pathetic. This applies to both games, but at least in ME1 there was Citadel, which is just ridiculous now.
So where does this game excel in the end? Just the graphics? The money spent on all the actors? Will anyone be bothered to replay it in 5-10 years?
Surprisingly I still enjoyed ME1 a lot, and did complete it. But I'm not sure I want to spend any more time with ME2, it already feels extremely repetitive for the reasons stated above.