me military wise i wish u could research and invest in a unique tank for a region. instead of having to buy a t-80 for example invest in ur own. if u have researched reactive armour u could add this to a tank along with spaced or composite armour also spaced armour on any unit u wish. or u could research a unigue unit for ur country for each catagory infantry tank recon artillary air supply etc etc for all branches.
I don't know how realistic this would be, only 11 nations in the world have actually gone from the drawing board to production with tanks: Brazil, France, Germany, India, Israel, Japan, Russia/USSR, Sweeden, Switzerland, the UK, and the US. All of the others have either had help from one of these, revesed engineered or both.