Vasari RA, TEC insurgents, Advent.......
Returning armada, aside from being a nifty ability, can be used to generate wads of cash via reclamation or just nuisance value. The primary problem is that this cash is not affected by fleet maintenance. Ok fine, TEC also gets free nuisance units which don't apply to their fleet count via the rebels, and the pervasive economy to reclaim the bucks. Advent gets.....5-10% additional faction, which, while it does affect economy, is still affected by fleet maintenance, and the only source of free units is the level 6 ability of one of their capital ships.
As advent seem to specialize in turtling, it seems a natural fit would be for a max econ tech to have the construction drones to place free turrets filling out the leftover tactical slots when they are not busy doing other orders. The penalty, of course, is that they place them a bit randomly around the place, you have to pay to put them where ya want them. Make the refresh time for new construction equal to the refresh time of the vasari DA ability. This gives a nice annoyance value free unit tech appropriate for the advent