You will find that TFB will be tuned similarly to as when you were level 50 - so if you havent beaten the council, you probably will still have some work to do.
The last fight, TFB, is a lot harder, needs better gear for sure.
I have to disagree here.
The Dread Guard is significantly
easier than it was pre 2.0. I suspect this is a result of (correctly played) raiders doing more damage/healing at 55 even with 63 gear and the stat curve changes.
The last fight is only "harder" insofar as the adds in P1 have significantly more health and required both DPS to deal with them, and the irregularities have higher health, so you will probably have 1 or 2 up for a short time after the phase ends unless your DPS have geared a fair bit. The rest of the fight is, once again, easier than the 50 variant was.
It will be hilariously easy in 72s, but that's what Nightmare is for.