Yea, America's not bad, but just rather passive.
Leader Ability: Roosevelt Corollary Units on your own continent receive +5 Combat Strength. Cities with a National Park receive +1 Appeal to all Tiles. Gain Rough Rider Unique Unit at Rifiling.
The combat strength bonus is basically the bulk of what makes America good and allows for strong defense and early conquest all of which is critical to Civ 6. It also makes perfect sense since the doctrine basically is not about non-interference, but that only America was supposed to do the intervening.
The National Park bonus is pretty lame. It translates to 4 tourism, so it may be a 33-50% increase if all tiles in the park is charming, but much less if it's actually a decent park. This basically ensures consistency, but since Naturalists are so expensive, it's not like park spam is even possible most of the time.
Finally the Rough Rider has to be hard built, and thus that probably won't see much use.
Civ Ability: Founding Fathers. All Diplomatic Policy Slots are converted to Wild Card Policy Slots.
Transforms a useless policy slot into a better one. Though it has no effect on Autocracy. As Diplomatic cards get better late game, this policy becomes much less useful.
Unique Unit (Civilization): P-51 Mustang. [Stats: Nobody Cares].
Really nothing to talk about, since fighters have no use currently.
Unique Infrastructure: Film Studio. Unique Building that replaces the Broadcast Centre (unlocks at Radio). Costs 525. Provides +100% Tourism from this City starting from the Modern Era. Provides +4 Culture, +1 Citizen Slots, +1 Great Artist Point, +2 Great Musician Points and +1 Great Work of Music Slot.
As with all t3 buildings, the base building is too expensive and terrible to really consider in the first place. Great Musicians also take forever to get and aren't that great. The Film Studio is better but requires an annoying conditional since not all civs will be in the modern era+ especially if you went to war and crippled some. And then America's abilities favor war too.... This might speed up some wins, but in a lot of cases you might as well just skip it.
Still quite strong at times, and recommended for beginners due to the solid early game. Unless you roll a dumb map where the continents split at your capital (yes that happens), it should be pretty easygoing.
Well, anyhow, fired up some starts and rolled a good one as America (Emperor/Fractal/Normal/Yadadada)
The game can't be bothered to give me a legit luxury most of the time so I just settle on the olives. Gorgo is just next door and attacks with everything, but since I'm America, all it ends up doing is giving my slingers experience. America should probably be more likely to open with early slingers since it's easy to boost archery with them.
I have to take Gorgo's capital because all this fighting sent me into a Dark Age... and then an emergency gets declared on me (But, she started it!) Her last city is a small one and succumbs to loyalty, giving me 400 free gold which is nice though not necessarily as game ending if you succeeded against a target early. I revive Gorgo to stop Khmer from taking the city, and to give tourism but I have to get rid of the Khmer's influence, so more war...
If I was still in a Dark Age, could have stacked with Twilight Valor. Even warriors would be decent.
I turn my attention to the Netherlands but I notice something is creeping up to my capital. It turns out Montezuma was acutally next door but he somehow hid himself until like turn 140 and since I was too involved in wars, didn't notice. Though it seems like Barbs crippled him so he's an easy target. Would have been bad if he showed up early, so thank the barbs.
This spot is great National Park bait. I even built a neighborhood. But they just cost too much faith and I only got 1 park.
And the game ended before any of the uniques came into play.
Capital @ end
Sparta
Also built the normally useless Potala Palace at the end which is basically a wildcard slot for America. I put... a diplomatic card in. It might have been more useful if I didn't waste the GE on the always useless Ruhr Valley, but hey, for the sake of completion!