I’m very happy that you seem willing to change things! I do think that DK needs a whole class rework.
However…one massive change that frankly needs to be made is to killing machine - you are incentivising frost DKs to built crit but their main mechanic completely nullifies crit.
On my opinion either you make killing machine obliterates damage scale with crit like chaos bolt or killing machine massively increases the damage of obliterate and makes it frost damage but doesn’t garuntee a crit.
Both oblit KM and Frost Scythe should absolutely do that, i’d even go out of my way and make it so Sudden Doom also scales with crit for UH also.
The other option they could do, is that KM don’t make oblit 100% crit, but something more the line of base damage being buffed, and our KM oblit hits even harder when it does crit from us stacking critical strike.