I was curious as to whether it was potentially efficient to use lower mana / lower damage spells instead of the most recent single target DD spells as a means of controlling agro, so I pulled some numbers into Excel. Nothing here is very surprising, but the answer is a resounding no. I didn't include spells with an additional effect (with the exception of low resist, as that impacts overall damage), nor did I include AE spells w/ damage for potential max targets. I might get bored and do that later, I guess.
At any rate, the link to the doc is here. The lower the Dmg / Mana ratio the better.
https://docs.google.com/spreadsheet/...TBEMWp3V2FkeUE