Here's a controversial one, most likely. I bounced so hard on the combat in ME1 that I've never been back to the series. No real opinion on it at all beyond that. If I had infinite time and energy, I'd probably go back and try it again, but I've never had a compelling reason to.
It is really weird to look back and realize the main reason I enjoyed Mass Effect so much was because I turned down the difficulty to narrative mode and treated it more as a branching path visual novel than an action shooter game. I hadn't really analysed it from that perspective before.
I watched my partner play the trilogy recently, and after she was done I HAD to show her Gears of War 1; a "pretty good" example of what over-the-shoulder combat/movement in mid Oughts could be like, and that came out a year before ME1. The entire time she was like "ugh I WISH I had that!!"