X1 and X2 were great X3 not so much.
Ian McKellen did a good job as Magneto. He was never meant to be outwardly intimidating, but somewhat conflicted as he still holds Xavier as a past friend and held to his own ideals shaped by his horrific experiences, he is on the side of mutants after all and the X-men are mutants.
The first scene of X2 is incredible, seeing crawler bampfing everywhere. I never thought I would see that in a real live film and was done really well.
I think Jean Grey could have been cast better, they needed someone more demure and innocent looking but can kick ass but she was not too bad.
The story revolved more around Rogue and Wolvie and the two leaders Magneto and Xavier. That's probably why Cyclops was underdeveloped, you really don't have that much time to develop everyone. I guess they thought audiences would relate better to Wolvie versus Cyke.
I agree about rogue, but I guess to be fair, she was still a fish out of water, just discovering her powers at the start so it does seem fine to be vulnerable as her origin in the comics also depicts. Maybe they should have developed her more into the comic version in X2.
I thought Singer did a good job of it all, I loved some of the action sequences and I'm glad that he didn't use the shaky camera that some directors pass off as action.
X2 is my runner up favourite of all the Marvel movies with Spidey 2 in first place. I grew up reading X-men comics and I'm just amazed that I can finally see it on the big screen.