Aye the diversity of unit types in generals is so much better, and then Red alert the unit types are even better than that. I was never much a fan of the Tiberium series in C&C.
On the MP of this it has literally been a case of build some rocket men + riflemen, and 6 tanks.... hold the choke points of the extra tiberium fields... build 2 refineries, then tech centre then spam mammoth tanks... There is not really an alternate way to play GDI that is as effective. At least with Generals you had all the 'air' generals and laser generals with some diversity in the units.