by sfox
This largely matches what I've seen to be the most effective strategies as well and I'd rank them pretty much in the order that you list. One thing you didn't point out is that all of these require picking up a lot of wood early game to boost your technologies. As you mention, advancing your resource tech so you get +1 wood when you take wood is very useful for exactly this reason. I won't say the first level of that tech is an absolute requirement, but it is certainly very useful and should be worth at least 4 or 5 extra wood over the course of the game.The 'corn strategy' is the easiest and most reliable one as it is harder for other players to interfere with it. If you have a lot of corn you can always place your workers on the board. Paying extra corn to place higher up is better anyway, and when you can produce a lot of corn this can really pay off. It also gives you two effective ways to move up the temple tracks (action 3 and 5 on the Tikal gear) which allows for a lot of flexibility. I'm not saying this strategy isn't beatable, but it is very reliable and beating it with some other method requires a lot of very careful planning.
The building strategy works very well but is somewhat prone to interference if two players are both going heavily into buildings. The best buildings are often grabbed before you can build them, or the buildings you wanted to build get taken by the other player, etc. To me the building strategy feels like the most natural way to play the game as you are actively building things whereas the corn/temple strategy you might build only one monument and one or two buildings the entire game, spending all your time advancing up the temple track instead. Even with the level 3 building tech which gives you 1 free resource to build a building you may not always have exactly the right resources you need. A small misstep can really make the wheels come off with this strategy.
I find the skull strategy to be somewhat problematic as it relies on having a lot of workers. I really think you need 5 workers to make this work which means you also really want one or more of the buildings which reduces the cost of feeding your workers. Maybe I'm just not doing something right, but I've never won nor have I seen anyone else win using only skulls against another player that is concentrating on buildings or the corn/temple strategy. I'd guess it could happen if they managed to build the right monument, but it just seems to me that the time it takes for a worker to travel all the way around the Chichen Itza gear can be better used elsewhere.