Conquest timer needs to change

Besides, what is the purpose of a timer in this game mode anyway?

It's to make you fight to win instead of only fighting to cheese feats. Getting 4 Fractures per battles is pretty good when you have only 5 minutes. But If you have no offence disks and lots of survivability disks, you could instead get all 40 in one battle at full stamina, and then you could vary your squads for the rest of the sector, never having needed to try to keep up your fracture rate with a 30% stamina Thrawn. 

Actually, Leia, also: I don't use her for the fracture feat bc her ultimate takes too long to charge, and if I'm playing to win in 5 minutes and the Ult isn't charged for the first 3 or 4, by the time I get there I've killed a couple enemies and more of them are low health and killed by Leia's AoE. She simply gets fewer Fractures than Thrawn in the current mode. 

But if you could play Leia for 40 minutes with lots of healing and no offence, you could repeatedly use her AoE fracture and slowly ramp her mastery (thus her damage) and eventually kill the enemy with only Leia doing damage. I completely changes the dynamic and makes energy cost per battle slightly less relevant and Stamina hardly relevant at all. 

That is kind of my point though. This is not really about whether a battle is winnable or whether better counters exist.

A match can still be beatable and the timer can still be poorly designed.

If the AI spends a huge part of the match taking long boosted turns before the player can even act, then the timer is measuring animation/AI turn time, not actual player decision-making. That is the issue.

So even if the answer is “bring a better team,” it does not change the fact that the timer feels bad in battles where the AI plays for 20–30 seconds straight.

Better counters and better timer design are two separate discussions.

Besides, what is the purpose of a timer in this game mode anyway?

I have never had a problem with conquest timers. You probably aren’t taking the right team’s in because 

A. You aren’t aware of the good counters

B. You don’t have the right teams to begin with, which is fine, but would explain your troubles