Ooooh, a riddle, I like riddles.
...crap.
In Mass Effect I ran into the most interesting character I've witnessed in Wrex. It was a joy having him along.
WHAHAHAHAHAAAAA!!! You cite WREX as an interesting character? The bipedal frog-dinosaur who spouts one-liners straight from Die Hard?! This is too good.
In Mass Effect I had to do difficult choices, even when I tried to stay loyal to one side (Paragon/Renegade).
Difficult choices? Are you kidding me? You had the good option, and the evil option. There was absolutely no gray, not like in Mass Effect 2. ME2 actually forced me to think about the merits of the genophage, and I still don't have a clear opinion on it.
ME1, on the other hand, was so clear-cut it was almost stupid. A good game, but far inferior to ME2 in terms of alignment.
In Mass Effect I enjoyed seeing my characters interact with each other, with chit chat in the elevators.
Oh yeah, great. Each character had about 3 conversations about absolutely nothing. Oh hey Tali, what's up with your immune system? Laughable.
There is more character interaction in ME2. Heck, the different characters actually acknowledge the other's existance, and not in some cheesy elevator scene, but by actually TALKING TO AND ABOUT EACH OTHER. I know, such a step downward from the great deep RPG ME1 was, right?
Most of the chatter in ME1 was generic, meaning every character says almost the same thing no matter who you bring. Brrr, sure is COLD on Novaria, right? Absolutely horrible.