If you can bare to wait for I7, then Thugs are ranged and the 3rd teir pet works in melee, the +damge it get from Fury over time and the level 38 power in Posion with see you dishing out very nice damage.
Thugs seem to be a great set for the /poison side, specialy due the lvl38 power and the 3rd pet (melee). I'm a 34 bots/psn MM, once i hit 38 i will let my bigboy get the pbaoe debuff power and i just send him in the heat of the battle, having 2x heal of the protector bots and a fast spamming poison heal you can keep him alive very easy, used it alot already for Elite boss tanking. 2 bubbles give him extra defence, poison also have a minor-resist buff to any mez-form.
I do have both hasten as stamina, specialy when you start spamming your heals your end goes down rather fast. Only single target debuffs isnt realy a big issue, most powers recharge quite fast with hasten to debuff several mobs at the same time. They execute very fast, give big debuffs and last quite long.
And the lvl35 psn bomb i believe gets a bit of love in Issue7, so helps a bit extra. 
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I know I've already passed you some info about robotics, Chaplain, but there's a couple of other things I haven't seen mentioned.
1) Ranged Pets are pretty much all DoT based. The Bots all have single hit attacks, but most of their damage output comes from DoT, so you don't get any of real 'big hitters' although an AoE immobilise + Incendiary Swarm Missiles from Stompy could be fun in I7 
2) This is the major annoyance for me a MM. The damage dealt by pets (or at least by my robots) seems to have a half second to one second lag on it before it's applied to the targets. So you can often find targets being flattened by the Brute/Stalker/Corruptor's big hits before the massive stack of DoT ticks your pets just launched are applied to the target.
TBH, when it comes to MM's, try one to level 25 or so. By that point you'll know whether the AT is for you or not. Some people like it, some people don't. It's not like playing other AT's.
Warning:
The above post may contain Cynicism, sarcasm and/or pessimism. If you object to the quantities contained, then tough.
To all and everyone who knows about Masterminds. I need your help.
Im shortly to roll a MM with an ingame friend as a 1-50 Duo. I want to roll something different without completely gimping myself. I have come up with the concept of Mercs or Robots with Poisons. I am not fussed about a cookie cutter, but I dont want to be running round with a totally useless solo toon, and nor do I want to be gimped in a team.
Poisons? Well I dont see many people using it, and certainly with its lvl 38 secondary power, poisons certainly favours melee types masterminds.
Does anyone have any experience with poisons and prefer ranged MMs?
Although my in game friend really doesnt like PvP, I will be PvPing and I though Poisons is probably one of the best sets for PvP, especially with a ranged primary.
Ranged Single Target Debuffs followed by an assortment of blasts from my bots/mercs = viable?
I dont really know what I am doing, so advice is a must. I just need someone to supply me with the confidence to go ahead with the Mercs/Bots + Poisons really.
Chap.