Yes, this has been asked for before ...
This already exists ... in a way.
Ice/Ice/Ice Tanker - this is one of my mains, and I run it like an Armored Controller
Frost at lvl 2 for the Slows. I slot for slows
Ice Patch lvl 20 - not the beast it once was ... but still good.
Freezing Touch lvl 22 - A hold that is nice to stack in close quarters
Frozen Aura lvl 26 - A sleep ... but it can put an instant stop on incoming dmg
Ice Mastery
Chillblain lvl 35 - an immob that I have on one build with the proc Chance to Hold 🙂
Block of Ice lvl 35 - Hold
Shiver lvl 41- a cone slow I have on a build ... nice to stack on Frost
Ice Storm - AoE Minor dmg, but -rech, -spd
This becomes about the mitigation of incoming foes and damage.
It does put you on par with Trollers ... kinda 🙂
Take a look at how other Tankers can do this