Mob Density Ratios?

[MitchEvans]

I've searched for the answer to this fairly basic question to no avail.

 

When building a custom enemy faction, what determines the ultimate mob density/numbers?

 

I understand that setting object and captive spawns to hard helps, but is there any particular ratio of Minion/Lt/Boss needed to optimize the spawns?  Some of my farms seem to generate only thin packs of mobs.  When I do get better spawns, I can't decipher what makes spawn density improve.

 

TIA.

[EmperorSteele]

I would think it's your personal difficulty settings more than anything.

[MitchEvans]

I'm set at +4/8.  After some trial and error, I think the best spawns come from using 3/2/1 minions, lts, bosses.  Perhaps keeping those constant (e.g., 6/4/2, 9/6/3, etc.) is the answer.