I think 3D is not the reason that the CnC series went downhill. 3D can
actually be used quite well as it allows some more graphical freedom,
and with a good default camera stance it isn't essentially different
from 2D.
What I believe the CnC games were so strong in is their story and how
it was implemented with the gameplay and gameplay elements. Take
tiberium - not only was it a key element in the story, it also was the
resource for your army and harmfull to infantery making it even more
than just a steady source of income. In Tiberian Sun they used it good
just as well introducing the Forgotten, the idea's behind Tiberium and
all.
That lacks in most RTS these days. Generals played ok but I was
disappointed by the storyline enormeously. It isn't worthy of the CnC
name at all. Recently I bought Codename Panzers: Phase one and though
it played nicely and had a great deal of detail, it's story lacked just
as well that depth that I liked so much in the early CnC games.
Red Alert was fun for me too though I felt it was too much just a mod
of CnC. Red Alert 2, although funny at times, felt way over the top.
The later units just lost every touch with reality which made the game
so much less believable to me. Tanks that are destroyed by infantery as
cookies... Buildings being chrono-erased... not really my taste.
/CnC rant... I just loved those first CnC games and it's a shame there's no good sequel to them these days...
Create-ivity - a game development blog