All the Sheperd butt kiss is kind of annoying...
Anyway, for me it seems like a real mixed bag.
I kinda wish there was more of an actual story to this game. The most intense parts of the story, from my perspective, included boarding the collector ship and then having the Normandy boarded. The latter of the two was actually really cool to play through, thought it could've been done better script-wise, and if you didn't have to go through loading screens every two seconds.
Level design is also another weakness, in my opinion. For the most part, they're all really well detailed and reasonable, but occasionally things just stick out as completely stupid. For example, on the mission where you try and recruit Okeer and end up with Grunt, it just seems so much like an artificial, undetailed linear mess. It sticks out from everything else, it's so bad. It'd be less noticeable it you could actually fall off of the ledges, but it just becomes so apparent how linear it is, which I don't like in levels. Also, the Freedom's Progress and Horizon colony maps: What kind of moron designs a town WITH NO ROADS? Sure, you have hover cars, but to have a place where the only way to get from point A to point B on foot involves romping through people's houses is just stupid. Heck, even if they did have roads and more reasonable paths, they weren't noticeable after three playthroughs. (I will admit that Horizon was better with this, at least having some kind of walkway and courtyard) Still, I liked Omega, barring the quarantine zone, and the Citadel levels plenty.
There were plenty of things I loved about the game, but I forgot what they were while writing that.

I'll just edit them in as I remember them...