One warning about techs: be sure you check their costs.
Unlike in regular Civ, the cost of the techs in each column are NOT all similar. They vary considerably. In fact, after you research a couple you might find that a tech that is now accessible in column 3 might be cheaper than one in column 2 (and so on, across the tech tree).
Example (numbers for noble difficulty, standard speed): Hunting, in column 2 of the tech tree, is quite expensive at 598. Sailing, in column 3 past Fishing is "only" 416. Other than the religion related techs down by the bottom of the tech tree, Hunting is the most expensive tech in column 2. It is, in fact, more expensive than any tech in column 3 (the most expensive of which are Bronze Working and Construction which are both at 520 and the least expensive of which is Festivals at 234). This does not mean that Hunting is not worth researching - it is a tech that gives you some good stuff (like a recon type unit that has a higher base strength than a warrior). Just be careful not to research it before you research some cheaper techs that allow you to improve at least some of the resources you have available to you (if course, if the nearby resources include some that need camps then hunting is better than it otherwise would be since that is what enables camps).