My current arena team consists of Bastila, Ezra, Old Ben and Kanan. I'm only level 84 and haven't unlocked GMY yet, who will eventually take the 5th slot. Kanan will be replaced by Revan down the line. For now, I could either use Ahsoka or Anakin, who are both geared up and ready.
Anakin is faster, and I could amp his speed up to 220 with Ahsoka's current mods. But Ahsoka's basic does more damage and her special can be pretty brutal when it crits. Her healing is usually pointless, but can come in handy every once in a while. On the other hand, Anakin's area attack has its uses, especially in combination with Righteous Fury.
I'd be leaning towards Anakin if it wasn't for the fact that Bastila almost always buffs him instead of Ezra on auto / defense. She seems to have a thing for the tallest guy on the team (or whoever stands in the upper right corner on offense), unless that person is a tank. When I swap him out for Ahsoka, she buffs Ezra at least half the time on auto.
What should I do? Go with Ahsoka, whose speed is still at 176 despite +83 speed mods, or pull off her mods and put a 220 speed Anakin on the team? He'd be the fastest team member. Not sure if it's a good thing when he goes before Ezra (217 / +86) and Bastila (208 / +88). I can't make either of them any faster with my current selection of mods.