Yes, Hamis can be slotted in pets and I do so with every mastermind for maximum effects and to fit in other enhancements
Cytos in Enforcers
Cytos in Prot Bots
a Golgi in Soldiers, Gargs and cats
etc and so on
Also, Endurance Reduction reduces the cost of the summon, as well as the endurance spending that the pet does.
Primary uses in say, tier1 wolves:
Nucleolus Exposurex2, 1 random acc/dmg/end pet dmg IO, 1 raw end reduction IO, 2 random aura buff IOs. Call to Arms, Sovereign Right, etc
Other uses like the Commando:
Nuc exposurex2, 1 raw end reduction, 1 OF KB to KD and 1 Mark of Supremacy end/aura buff, 1 random aura buff IO. This turns all the knockback happy powers into Knockdown while getting the most out of his end bar
My Gargs are slotted:
2 nuc, 1 acc/dmg/end, 1 golgi, 2 random buff ios. The resistance aura they give off is not huge and I prefer the extra healing as a demon/thermal