I have read a few posts on arena and thought I'd add my long winded two cents in about it. I'd like to start off my saying that I have only spent 10$ on the game (5$ starter pack, and 5$ daily crystal package) along with some very good luck from bronzium cards (4* Old Daka, and a 3* Luminara.. don't hate) and with this, I float between rank 1 to 25 depending on the time of day and RNG luck. The team I currently run at lvl 43 is: Luminara, Old Daka, Dooku, Consular/Chewie, and of course, the Jawa. I know, just another cheesy 3 healer team, but it's what I have been given.
I have read a bunch of sob - posts about "OP dooku" or "OP Barriss" but in my opinion, they really aren't bad to deal with. My strategy for the current cookie cutter team (barriss, dooku, chewie, consular, random)that I have been very happy with is to open on Consular with basic auto attack till barriss heal is used or consular is dead, then switch to Dooku as long as chewie taunt has been used, and unload cooldowns. Dooku doesn't have much of a health pool and will go down usually in less than one turn rotation. Other than that, I just ignore barriss and chewie till the very end. Barriss does kitten food damage, once her heal is down she is just a very minor heal proc from her auto attack.
When fighting the chromium accounts, watch for the low to mid health hard hitters like Darth maul or the fighter pilot that hits like a train. If you see these type of heroes blow cooldowns to kill them before they can unload on you.
For lower level players, focus on ranking up asap in arena, refresh your opponents a few times to get players just a few ranks higher on the ladder, make every battle count, and fill your A team characters gear slots asap.
This is not a brag post by any means, I am only linking pictures for validity. I am still very new to the game and have a long way to go, just giving advice on my experience thus far.
Arena rank 30 min ago-
My current roster:
Ps: thanks to players like slushie, whipit, Iam2awesome and Qeltar for all the helpful and insightful posts on these forums. Just wish we had more Dev activity here.