As a FTP player, this is getting harder, and it demands more time. My experience so far, the highest tier in STR challenge is now impossible to finish (though I won once. ONCE. And it was by pure luck, I guess ) Then I managed to finish tier 4 AGI challenge with debuffers & stunner 7* phasma, *6 dooku, *6 poggle, 5* JC(for emergency heal) and 4* Talia. Then I think I'm gonna pass on INT challenge because I don't even have a 6* tank and none of my toons will use the reward items yet. For GW, it takes too much time now (and patience) I hope we can regen the protection bar. I have 5 max level (lvl73) toons whose protections are all gone, then the opponent's team is lvl 75 with full protection, high speed toons and with Dooku as leader...so..GG...I've sacrificed suicide squads just to take out damagers on the last 4 GW rounds...15 of my toons died in GW and I make sure their deaths will not be in vain. But I have won the GW. I have avenged them.
So far, I don't have much problem in Arena as of now. I'm fine with rank between 150 and 200.
The protection thinggy is kinda weird tho.