What ARE the combos?
Also, Vasari sounds fun

Do Vasari have the STRONGEST ships or does that belong to TEC or Advent? Does TEC's fleet fail in an even fight? (say, a battleship vs a battleship, or a frigate vs a frigate)
Advent Abilities:-
Radiance Battleship: Animosity - Makes all enemy ships attack the Radiance only and ignore all other friendly ships.
Rapture Battlecruiser: Vengeance - This ability can be applied on a single friendly ship. Whenever that ship takes damage, the enemy ship attacking it takes a multiple of that damage.
Progenitor Mothership - Recharges the shields of any friendly ship.
Iconus Guardian - Diverts 33% of the damage taken by all nearby friendly ships to the Guardian's own ultra-tough shields.
Disciple - Steals antimatter from enemy ships and transfers it to friendly ships.
As you can see, the Advent ships abilities complement each other in harmonious combos which can turn enemy ships into your puppets. Along with the best abilities, the Advent also have the best shields, the best strikecraft/hangars/carriers, and the best culture-powers. Their weakness is their complete dependence on antimatter and crystal, and their weak hulls(if your shields are depleted or if they are pierced by Phase Missiles, your ship is dead).
The Vasari have the toughest armor, best hulls, special shield-piercing Phase Missiles, self-built Phase Gates(for direct travel to anywhere in a single jump), and special defensive stuff. Their weakness is their weak economy, and their expensive ships. IMO, they also have the ugliest ships(The TEC has utilitarian industrial looking ships, which are fine, and the Advent has sleek shiny ships, which look nice, but the Vasari have... big bulbous space-whales).
The Trader Emergency Coalition(TEC) has by far the strongest economy and cheaper ships. They thus can have a larger military than the others, but their abilities are very plain. Their ships are jacks-of-all-trades but masters of none. They use conventional warfare, unlike the Phase-twisting Vasari and the culture-king Advent.