Since you will be invisible soon enough, you can go for concentrations (concentration 3 buff and astra lord focus) and damage skills (Astral lord Lore, tactic lore and ancient magic) first.
1 - Damage and attack value +xx% with rings damage +xx-xx and attack value + xx% or damage +xx% and attack value +xx%.
2 - Shadow veil is very low (10%) and reflective emanation/nether allegeance are around 30-40%, which mean +100% to regen times. The shoulders from Infernal Torment offer a good stamina bonus, and you can forge stamina bonus if you want to lower the penalty from buffs.
3 - Officier Saber or Khandar's slicer.
4 - Frenzied rampage in a combo, Rousing Command + Augmenting guidon + Killing Spree in another one, Skeletal Fortification in the third one, and rallied soul in the last one.
5 - Frenzied rampage around 3-5s under the buffs
Highlighting number 4 at the bottom you said your combos include frenzied rampage by itself? got the rousing command/ augmenting G /and KIlling spree. uh, then skelatal fort by itself? and then rallied souls by itself? Not really sure what you combined with those three. Also, is cross combining a good thing cause then you lock yourself out of a double attack. Personally I like to combine guildon and skelatal fort on my death warrior build. I guess since needing frenzied to attack that wouldn't be a good idea?