no dodges happen, and I'm sure its not "always".
you were set in your arena group when you joined arena and those are the people you are stuck with for life.
The problem with your team is synergy, not GP. ATF is not the best on defense, the AI just doesn't handle her kit well. Chirruit is a good toon, but only becomes great when baze is there to protect him. no auto taunt or GK means your team is wide open when the attack comes in.
commit to 10 attacks a day and you can climb higher in arena and overall may see yourself drop less overnight. try to avoid high movement areas, near payout increases.