One final thought re unbalancing the game. The SEALs are intended to be an unbalancing unit, as are f-15s and Stealth bombers. Creating a unit simply to have the "kewl" name in use is silly. If you have any of these and your opponents do not, then warfare has tilted sharply in your favor. Your opponents can always create bomb-vest wearing mal-contents. That is what has happened through-out history. Combat un-balances (phalanx) and re-balances (legionairies with coordinated training allowing them to suck the phalanx in and then split into three units and hit the flanks). Anyone care to ask the (un-balancing) French Knights what they thought of the (re-balancing) English Yeomanry on St. Crispin's Day? You only build the units you can/need to swing battle your way.
Thus SEALs, B-2s, F-15s, F-22s.
Thus SEALs, B-2s, F-15s, F-22s.