Build Setup -- Currently Level 94 in HC
This setup assumes you have a CTA for your swap giving you +1 - Notably to the Death sigil and to Enhanced Entropy for radius.
Level 27 Enhanced Entropy grants a radius of 10 yds, more points will give you 12.
The image below shows exact points w/o items that grants 10 radius. Putting 5 points into abyss will give it 1 additional radius.

I did not build this setup with the perfect inventory, gear etc and the main point of discussion is below.
PREMISEAbyss to pull monsters together and to keep them from running.
The most annoying thing I encountered with any summon build are runners and many smaller mobs that ... overwhelming in number that it slows down clear speed.
TIE IT TOGETHERWith max Death Mark - Goats run 25% crushing blow , Max goats for extra damage. Goats have CLEAVE as well.
Bind with Curse + Fana.
Sigil of Death to deal almost instantly pop any group ( max radius is very preferred )
Abyss to keep mobs grouped and unable to cast or run.
FEEDBACKI'm reaching out to you to see if anyone else has tried or is running something similar and your experiences with it.
Is there something that you could use to better assist your summons to improve clear speed. ( excluding runewords from gear or mercs ) (( UNLESS there is a niche item that grants you a specific utility not already granted by your summons ))
THANK YOU