pretty simple build, utilize life leech and vitality dmg for starters, all you have to do is buff, hit and spam 1 skill. been playing around with this build on ultimate and had much success with it so far at the last act.
its my first build doing alone and wondering if there is anything that can be done better thanks 
https://www.grimtools.com/calc/r2BG8xBV
note i could not find my original green boots i use, the res with the right boots should look more like this :
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You should start by trying to increase your offensive ability/defensive ability, armor absorption, changing your skill layout a bit.
Here is something you could work towards https://www.grimtools.com/calc/YVWqe9nN
I tried to keep what I felt like your goal/style of build was. At a glance you might think your damage is lowered as the weapon damage shows a lower stat. But with all the extra OA and crit damage the above link sports it will be far superior in terms of overall damage. Also I removed whirling death, and also toned down the total proc chance of Sheers/Quick cut to 15%. This was to increase the number of reaping strikes/execute/necrotic edge procs. The weapon pool skill total chance = 100 under the new build. Also the amulet I added to the build is craftable, and the blueprint is purchasable via reputation with barrowhelm.
I took shadow dance to 12/12 it is a hugely powerful defensive buff to your build. I also grabbed Mark of Torment and Blade Barrier. These two skills are fantastic for saving yourself in moments of duress. (oh shit buttons) Siphon souls is a great aoe dot/debuff/heal.
If you do not like the life drain from Dying God (the life steal the build rocks should be fine covering it) drop the last 2 points and the green node to take Hawk for extra OA and crit damage.
I know I added a few more buttons, but they don’t necessarily have to be used.
