Mass Effect is awful and you should all feel bad for making this series popular. I bought ME and ME2 for $15 combined a few months ago on Steam, and I was shocked at how boring, incomplete, and hackneyed Mass Effect was.
Let's talk about the story. A lot of it is just plainly ripped from KotOR. Council = Republic. Spectres = Jedi. Reapers (what an amazing name, by the way) = Star Forge, Prothean = Rakata etc. The story isn't some deep and interesting space drama, it's your very generic "save world from horrible unstoppable force." The characters are also a mish-mash of tropes we've seen a billion times. Ashley = military bitch, Tali = Kid good with machines, Liara = naive smart girl, Kaidan = generic guy, Wrex = anti-hero, Garrus = guy no one talks to. We've seen these tropes a hundred times before and Mass Effect doesn't do anything innovative with them. The races aren't interesting and nothing seems alien about their cultures or their attitude, they are just ugly humans.
The paragon/renegade system is outdated and only gives the illusion of choice. Basically be a dick or be a knight in shining armor, there's no in-between. After playing The Witcher, I don't know how people can stand such black and white and generic choices. I hate how the paragon/renegade choice was always in the exact same spot on the dialogue wheel. Bioware didn't even bother to challenge us to think about our actions, they just blatantly pointed out which was good and which was evil. The rest of the spokes on the dialogue wheel were just asinine comment about irrelevant stuff you didn't care about. This stuff seemed innovative in KotOR, but gamers should want more from these types of RPGs now.
This game toted that you could explore the vast and exotic landscapes of the galaxy. Yeah, I guess you can if you consider different colored skies and the same mountainous terrain as "exploring." There was nothing on those planets you drove around on. Sometimes you would find a crashed ship where you could loot junk to turn into omni-gel, but other than that each non-story side planet was the same. The only reason to visit them is to do the sidequests, and god were those terrible. "Shepard, this is the UNC commander... I just drank a bottle of Nyquil so if I sound like I'm about to go to sleep that's why. I want you to explore some shithole and uh... shoot some people. Honestly it will be pretty easy but it will be boring as hell so that's why we're sending you." Not one single planet was creative or exciting to explore. Compare ANY planet in the first KotOR to any planet in Mass Effect and it's night and day when it comes to quality in terms of interesting locals and things to do and see. Every main story planet you went to in Mass Effect was a bunch of boring ass metallic corridors.
And the actual gameplay is just boring. Throw biotic, pew pew. You fight the same handful of people OVER and OVER again. I think this game has the least variety in terms of enemies in any RPG possibly ever.
There's some other stuff I could probably complain about, but when I was playing Mass Effect, I kept telling myself "it gets better, once you beat it you will have a Buddha-like moment of enlightenment and understand why everyone loves this game." Nope. At the end of the game I was just left shaking my head at how people have latched on to this hollow, brain-meltingly boring series.