I have to say that I really loved CC2. I played that grand Campaign through three times, over about 60 hours each. I couldn't wait for CC3 and was extremely disappointed. CC4 was more of the same, and worse.
What I liked about the CC series was that it was real-time, but the battle developed slowly enough, and I had a small enough number of troops to command, that I never felt it was a click-fest. The infantry seemed capable of taking care of itself -- where I had to babysit was with the semi-braindead armor. I think with their growing emphasis on armor the weaknesses in their code began to really show. As a primarily infantry game, it was great. I had some of the most memorable moments in my (long) gaming career in Market Garden: a wounded sergeant single-handedly bayonet-charging and defeating a surprised German Scout unit in the woods just in view of Nijmagen, anabling me to barely capture the bridge before the sun went down; a cowering PIAT assistant hunkering down in a building with his leader dead and a Panther several meters away, finally getting up and taking his last shot, destroying the tank and stopping what had been turning into a major punch through to Arnhem; the lone .50 cal team in the farmhouse fending off swarms of German infantry, corpses littering the ground just meters from the window.
I lament the decline of the CC series precisely because I loved it so much (despite its flaws) and saw the potential it had to become something even better. Unfortunately, it seems that the Atomic team have no interest in taking the series in that direction. I am really glad for CM, and I know I will love it to death, but I just can't bring myself to bash one of the very few RTS games that really hooked me and made me believe the genre had something valuable to offer.
Having said that, I still think that if the data could be made more accurate, the lethality of weapons fire could be toned down to a more realistic (if less gee-whiz) level, and the tactical AI for the armor could be improved to the point that tank commanders could take reasonable care of themselves, it could be an amazingly fun game to play. I just don't see that happening.