Well, 70-80% of new players choose TEC for their Human looks. And that's one of the reasons they are slow to learn with out other player's help.
Not that the TEC is 100% weak. They have some advantages.
The TEC is economy-based. If you're attacked and have a relatively small fleet, you could keep pumping out carriers and Anti-Fighter ships (if under spam attack) relatively quickly.
The Advent is realy focused on power. The problem is, Vasari and TEC ships are much weaker than Advent ones because Advent have more shields than any other race. Shields are harder to take down than hull. The way most Advent players fail to win some games (most of the time spammers) is becasue they don't research. They know beefing up their already strong combat vessels would be pointless and a waste of money. Which is wrong.
Soon the Vasari and TEC players will develope countermeasures to defeat Advent forces easier. So if you're Advent, chances are you're in luck if you keep researching. It will keep you above all other players and at the top of the food chain.
The Vasari, for the most part, is also economy-based, but has some pretty good combat and support vessels in their arsenal, which is key to win losing battles.
And remember, when you're winning a battle/game, don't let up on the pressure. Keep assaulting and raiding their planets to keep them on the defensive.
I'd make a better, long post with more details, but I'm just too damn tired from school today.
I'll post a better one later but for now, that should be good enough.