Based on early exploration, America's territory appears small, but very defensible. This gives me confidence, although England needs to be handled with care - they only appear to have one expansion path, and we're it. The Great Barrier Reef so early was great, since that allows population to grow to (about) 8 before unhappiness occurs.
I mentioned Tradition as a Social Policy option earlier, but primarily as a strategy of desperation: A way to magic up extra hammers and food to prevent the whole plan falling short. SevenSpirits touches on the fact that our Civil Service slingshot opens up a lot more sexy policies, and discussion of this is key to the mid-game plan.
Given some of the lurker comments here, it's perhaps worth trying to explain why I suspect we're heading the way we are, which in turn will inform "policymaking". My logic. I can't read Darrell's or anyone else's mind yet, so feel free to correct or add or disagree. (In the unlikely event that *I* sound convincing, remember this is still the blind leading the blind - don't be fooled by 3 days selective experience

)
Ages open up policies. It doesn't matter which tech takes you into an age. While it's not automatically true that later policies are better, from what I've read, that often is the case.
Over the next week or so, you'll probably read a lot about how "overpowered" City States are, especially maritime states, with their generous gifts of food. Simply put, it's more effective to convince them to gift food then it is for you to grow your own, even if you have to trade "the family silver" (quite literally in our case) to gain such gifts.
The medieval era (which for us will hopefully dawn with Civil Service) opens up... Patronage: A veritable toolkit for instant City State gratification. So if we can reach a relatively advanced age so quickly without needing Tradition, perhaps consider simply holding the points, and not establishing any early policies (I believe that's possible).
Now, you might ask why, given such promises of bountiful food, we're heading towards a tech that gives us a substantial bonus to, erm, food production? Good question. As I see it:
1. At this stage we don't know if we have a maritime state on this continent. But we do know that we have lots of river-banks. So in the worst case scenario, we have something to fall back on for food.
2. For pure mathematical efficiency, Civil Service is the highest research point tech that's realistically going to get discovered using The Great Library.
3. We're teching along the least warmongering, most research (and to a lesser degree economy) focused branches of the early tech tree, which suits the gameplan and America's lack of early unique unit.
4. While the tech path isn't military, it does at least have Pikemen at the end of it. Not perfect, but they will hold off most of what we're likely to see anytime soon.
5. [Added:] Chichen Itza for +50% Great Age length. The value of this depends on the value of Great Ages, which in turn depends on terrain and how much happiness you can muster. I initially overlooked it given our current position, but longer term it could be powerful.
(That's the theory anyway...)
Beyond Civil Service, it's worth understanding that production is poor at the outset, but crucial to getting things built. Later in the game there's a reasonable theory that says gold becomes more important. And also consider Golden Ages: These don't add a hammer to a tile with 0 hammers, meaning plains and hills are great, everything else sucks.
What this may mean is that our capital will evolve function over time: From food now, probably shifting to mines, maybe later shifting to gold.