Honestly speaking I haven't been able to tolerate any of the C&C games except the original and that add-on package. The AI on that was just well done and 'fairly' balanced whereas it seemed later packs just used cheap tactics, ai advantage overkill stupidity, and I hated to no end those underground stages in Red Alert 1. The underground really pissed me off like that one stage where the enemy got into your nuclear reactor thing, and you are given like 6 guys, a dog and a spy or something to evade a platoon of people, flame towers, and a panzer division...what the fuck...it's a NUKE.
C&C 1 I can play to death and enjoy the hell out of, always have, but can't stand the sequels sadly. That and then the old fun times I have with warcraft1 and 2 at the same time period...good stuff there.