I usually have my attackers run 7-8 dspa, then the rest of my military goes into offense. (usually 13+ epa/ospa)

so as a Faery attacker, that would be around 5 EPA for the same level of defense.

But since you are going solo, and not worried about war, you might want to run closer to 7-8 epa, then toss the rest into offense. Should give you respectable numbers.

DSPA = Defense Specs Per Acre
OSPA = Offense Specs Per Acre
EPA = Elites Per Acre