Red Alert 2 was definitely my favourite CNC game. I mostly played Soviets in the RA games and GDI in the Tiberian games. Generals I liked the USA's airforce a lot. I am also a bit sad about what happened to CnC, EA really destroyed the franchise by trying to make it a lame cash grab.
Also, the franchise has one of the most memorable themes in gaming history!
Indeed, that RA2 theme song was pure genius :)
RA2 is better than TS in many respects, but, as stated in the post, TS will always be close to my heart.
I liked to play GDI mostly, and either US / UK for the allies, or Russia for the soviets. As for Generals, I don't know why, but the game never really gripped me, even though I liked it alot.