That axe with high dps is old axe before .2.1 came out I'm pretty sure. Btw, you should use hammer for higher base dmg reasons. Have that hammer with ed% from glinting hammer or wd% hammer from ragnarok or mashochists wizard sword jaspered to warrior.
You can also free up slots. For move speed, we got sprint with 70% move speed (50+20% from hero points), Zealous for 20% move speed and dmg, and dexterity for 10% move speed with dodge and that. You already get 100% move speed easily without the need of those legend move speed slots. Remove the legend move speed affix and replace them with some other thing that will boost your dmg alot. Maybe things like push the limit , barbarian or so. It's up to you. Your momentum has 100% full potential at this point.
Pet wise, try using pathfinder. I think you'll love it. Replace one deadly strike for crushing blow and I think you'll like it for high floor. Of course, make sure mobs get grouped together for the explosion to happen more than once and multiplies dmg.
I'm pretty sure phalanx won't give you block anymore so I think you should replace it with some other talent, preferably not fanaticism or provocation though because taunt can break frozen cap off of enemies that already were frozen. Fanaticism is debatable to add. Fustigate is no harm though or cleanse.
Special skill up to you. Sword throw is good choice because of range reasons , with high dmg, and you can use every once in a while if you find the perfect opportunity. Sprint you know what to do with it. Oh special skill can be stealth or whatever you think is best.
You could try empyrean but that's up to you. Well, this is as much options I suggest you try. I'm sure this will help you gain alot more dmg . Sprint and nova as you might have already guessed is the main dmg in this, as well as arc beams. There some other options but I suggest you try finding them.
Also, what floor are you on and did you enable crit dmg only on options to see what the difference is. Initially, this build deals few Billion dmg but if frozen explosion happens, it should multiply and chain explode on enemies, with permafrost constantly spiking up.