Thanks for your support of the game! Unlike a lot of other games such as the Age of Empires series, there are not overall "tech levels" in AI War in the sense that you must traverse them outside of individual technologies. Instead, it's a very wide tech tree in general. If you use science labs, you can unlock any technology that does not have a still-locked-prerequisite. Wow, that probably sounded confusing.
In simplest terms, you start out with Mark I fighters, bombers, and frigates/cruisers. Right from the start, you can unlock Mark II of any of those ships. Once you unlock mark II of a given ship line, you can then immediately unlock Mark III of that line even if you have not unlocked Mark II of another line.
Generally speaking, in AI War you'll unlock very deeply in some parts of the tree, and not at all in others, depending on the game and your style. It's a "build your own civilization" thing where you won't ever unlock all of the techs in a single game, it's not even possible on the hugest maps -- so choosing where you want to allocate your knowledge is basically choosing what you want your "civ" to look like.
If you haven't done them already, I highly suggest the in-game tutorials. AI War is wicked different from most other games in its strategy, and you'll miss a lot of you don't opt to do the tutorials.
Glad you're enjoying the game!
