My version of America
Teddy's unique leader ability: Naturalists cost
25% less faith and are available earlier in the Civics tree at
Civil Engineering, +1 Appeal to all tiles in a city with a National Park. Gain the Rough Rider unique unit,
which replaces Cavalry and is available at Military Science.
(Reasoning: This streamlines Teddy's cultural bonuses more prominently and gives America a reliable UU to upgrade into. It allows for a faster naturalist for a cheaper price giving for an incentive for players to really capitalize on this and it feels smoother. The continent bonus is removed however a combat bonus is worked into the Civilization's unique ability instead)
America's unique Civ ability "Founding Fathers." Earn all
government legacy bonuses in half the usual time,
American combat units gain a +1% combat strength for every +2% legacy bonus earned while under the same government the legacy is earned from.
Example: An American combat unit gains +1% combat strength when you've earned a 2 legacy percentage points per government type. So if you're in 'classical republic' and have earned a 6% legacy bonus you're units have +3% additional combat strength while still in Classical Republic. Legacy bonuses are permanent while combat bonuses reset when the government is switched.
(Reasoning: This adds to a pretty weak bonus by adding a combat bonus. It gives the incentive to players to really prioritize and want to 'milk' America's unique bonus. As America adopts a government it learns and becomes more stable across the board which benefits the civilization in all aspects including militarily)
Unique Unit : Rough Rider
Culture is earned from kills. Gains +10

Combat Strength when fighting on Hills. Lower maintenance cost. Still retains the current combat strength and movement (67/5) but removed the continent restriction.
P-51 Mustang stays the same.