Doc Tsiolkovski
Deity
What about an improved ironclad? Build one that is really hard to sink. Was it not Americans that build the first ironclads?

Is that irony?
Sorry, but while the ships you're referring to - USS Monitor and Confederate Merimack (sp?) - can claim to be the among the first Armored Steam vessels to be built, the 'hard to sink' part is funny: The Monitor was also the first Ironclad to sink; not by enemy fire, but a small storm...
(No offense!)
Seriously, those 2 ships may be famous, but they are really no milestone in warship development. About every advanced nation would have been able to muster comparable ships easily, if they had seen any need for them. The HMS Warrior,now that's a different issue...
One more thing: Some of the units suggested in this thread are widely unknown in the rest of the world, and resemble more a national myth than an actually 'strong' military unit.
Best example is 'Minuteman': I know the rocket, I even know the 80ties Punkrock band, but so far nobody ever could enlighten me what's so special about farmers picking up a weapon and raly to defend their lands - about every nation in the world had something comparable at some point of their history.
Tomahawks (the cruise missile, not the mediocre WW2 fighter), Super Carriers and several bombers (B-17, B-29, B-52, B-2) or SR71 are widely known, but face it, for gameplay purpose they aren't better than the F-15.
The Abrams is clearly not superior to some other modern armors.
A useful unit would be the Sherman (same stats as Tanks, but half-priced), but that would be quite an odd UU.
So, best choice for me is a strong Marine or Paratrooper replacement; and surprisingly, the only altered UU in RaR is...the Airborne Ranger
