I gave Dox uber cannons as a joke, but it seems I accidentally balanced it. They need energy to shoot and do almost nothing to buildings and commanders. These dox have good aoe, but still take 2 shots to kill basic tanks and infernos can take several shots. You need dox to get that early map control and to counter t1 spam, but there's no point sending in big groups of them because 1 dox can kill 20 dox in one shot. It's nearly impossible to win with just dox because once you get a lot of these, you spend all your energy. Naturally with dox balanced, t1 air spam becomes a thing. I gave the missile tower an aoe uber cannon, but that still needs to be balanced better. The idea is air can still raid and defend, but won't be good over a base. You pretty much have to area patrol dox because you don't want them standing in groups. They can pick off fabbers and kill or damage swarms of units, but don't expect to take out a base with them. They can also be easily stopped by single-barrel lasers. The only way dox can kill those lasers is in large groups, which are easily killed by just one dox. You're going to want a good amount of tanks for taking land. These two changes mean the game can actually reach t2. Slammers seem to do ok against dox, but might not be as cost effective as t1 tanks. Levellers and shellers can probably help clear out the single laser turrets that tend to pop up everywhere.
I replaced the AI's land scouting behavior so that it area patrols dox correctly. The AI will never be as good as a real person, but this is a start. I should probably tell it to build more single laser towers too.