your weapon is your main problem, this is not LoD

best options:
ebotd TM - highest dps vs anything but diablo/baal/t5 heralds/ubers
eDeath Decap/Glorious - highest dps vs diablo/baal/t5 heralds/ubers, just a lil less dps vs all others
eReaper zod'd - best QoL (not relying on a merc that you can't reposition with tele) easy life and more than enough if you play on low-mid player count
If you chose botd or death, you can still use reaper on swap and spit on cta, cuz shifters already get more life than needed.
Angelics are fine early, but the higher your lvl the least relevant they get.
I like 2x BK, cuz they give a lot of ed%/ar%/life%/ias
and HL, cuz DS% is very great on builds that don't have innate crit from skills.
Yes, sunder will help, renewed bone break gives a lot of stats
I'd aim for:
-dr
life
frw
I use SS skillers, all of them with 7frw
just like BK's, they give a ton of ed%/ar%/life%/ias
great and cheap
fix your fire and light res with scs
cold dmg is irrelevant
you can fix psn dmg and curses by putting Cure on merc
the rest of your gear is on point