Mages have a hard time performing atm but its possible to do Rank 163+(highest possible stat drop) with a Mage. Looking at your Build atm... It seems you are not rly investing into any massive Dmg Sources atm meaning your neither go Aliments, nor Crit(normal dmg without crits is crap^^) nor you go for Projectiles. Also you Lack Defenses no block, no resistances, no dogde, no dmg Reduction passvies. Even 500k Forceshield can get 1 shot on endgame without any migation.
I would rethink what your Focus gonna be, if you wanna stay mage you will a good amount of suitable gear to make your self the killing maschine you wanna be. If you wanna go Aliments you should perk into it more, if you wanna go for big hits you gotta get your self Crit-Chance(40%+) and Crit-Dmg 400-500% or you perk into Projectile Dmg (Consuming Embers and Tear get massive boots from that).
As for Defensive Salvatory Anchor is a possiblilty, with just 2 Heavy Armor Pieces(around 720+1100) you can get about 60% dmg reduction vs everything and so make your Forceshield nearly tripple in effective value. Or you go if you are constantly on the move and can avoid most attacks adding Dogde Chance Score on gear and suitablle gear can get you to 75%+ Dodge but it would gimp your Max Force Shield Massively since you would need to use Gems to get it done + Branded Burst make 1 shots unlikely, or you somehow add blocking 90-100% on 75% efficience.
my 50 Cent