Construction Yard - reactivate destroyed buildings. Costs a fair amount of money and takes time for the building(s) to start working again. It would be nifty if multiple players could pay to reactivate buildings.

This would mainly be an addition for servers on which games can last over an hour, I suppose. And even then it'd take careful balancing to ensure that it's neither a "this is completely useless" nor a "this makes the game bloody boring" feature.

As for helipads, what purpose would they serve? Aircraft have unlimited ammo so far, and I doubt Westwood is going to change that. Sure, they'd look pretty and stuff, but they would also be pretty useless.

I do strongly agree that aircraft should come flying in from the "outside" instead of being produced/dropped off.