The problems of cold war era are plentiful. You can see that by playing modern warfare mod for coh1. For example it is really hard to model helicopters in coh type of closed in view. It would also be hard to make something around nuclear weapons. You would get sturmtiger type of weapon, either nerf it into no use to please competitive players or give it full power for casuals. And finally, it is hard to imagine more than 2-3 factions, which is a problem as coh has the tradition of dividing factions into two parties. I'm sure there is more, these 3 just came at the top of my head.
I'll try to respectfully debunk this in an effort to reinforce my viewpoint. So, I'll start from the top.
1.
It iss really hard to model helicopters in coh type of closed in view.
Why cant helicopter's just be treated as hybrid of gliders and air-support? They could be used in abilities only, as planes are currently. Some helicopters strafe with weapons, some drop-off stuff, etc. I think attack choppers would best be used as a loiter ability.
2.
It would also be hard to make something around nuclear weapons.
Dont include them. After-all, if nuclear-weapons start to be used, then its the end of the world, right? Add one more game (series) to the cold-war rts list, the war-game games dont use them, and nobody complains there. A good way to use them would be through a campaign mission, like the V1 facility in CoH.
3.
And finally, it is hard to imagine more than 2-3 factions
Well, I can think of must-haves for East and West.
1. America
2. EU (Not sure if should be split into separate countries or kept unified. Splitting would definitely fatten up the faction list but require alot more work.)
3. Soviet Union
4. China
There's 4 factions, equal to CoH's four. Some more could be;
5. South America (maybe some sort of union, its alt history after-all. Thinking of the Monroe Doctrine)
6. Soviet Satellite States (Same situation with the EU)
I think with a bit more thought, a really good foundation for a cold-war CoH is set.