Its certainly worth putting at least one acc in them as they have the standard to hits as if they were a player. Also taking into account that the T1 and T2 pets will be lower level than your foes you may find 2 accs in them a good choice
"Well, they found my diary today.
They were appropriately appalled
at the discovery of the eight victims
They're now putting it all together.
Women wrapped in silk
with one leg missing
Eight legs, one body, silk,
spider, brilliant!"
For my thugs mastermind, this is how I generally/plan to slot the henchmen...
Minions (one is equal to you, two is one level below you, three is two levels below you) - Three Accuracy, three Damage.
At two levels below me, if I happen to fight oranges or reds, they're gonna con red and purple to the tier1 henchmen, who arguably make up the backbone of your small army.
Lieutenants (one cons yellow to you at your level, two cons white to you, at one level below you) - Two Accuracy, Three Damage, probably one Endurance Reduction
The last one is apparently for when they get their level 32 powerup. Then, they use up their endurance very quickly, apparently. Of course, for thugs, you may want to slot for their Manoeuvers.
Boss (cons orange to you? Can't remember)
You COULD get away with one Accuracy, three Damage, but I'd rather go with two Accuracy, three Damage, and one Endurance Reduction. The final slot, as well as the one in lieutenant, would be after level 32 when they get the second upgrade which apparently uses up lots of their end as they suddenly get lots of new toys to play with. 
Ideon's Paragonwiki page
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Arc: 60092 - Supa Rumble in the Park
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-- High-Roller
As the questions says, it worth putting any accuracy in them or should I go for their secondary effects? i.e. Stun, heal, KB etc....
"Like War_Hero said, leave it as it is, it toughens up the softies." - Naz Nomad
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