Here's an update on my original build idea.
I got my Cu to 5 slots tonight. Added poison, then aura of nausea, and finally discord. (The DeBuffinator)
First impressions:
This seems to be a very good and viable build so far. Keep in mind discord started at 20 and I got it to 30 pretty quick-a lot faster than a player can. Some take-aways from discord so far is that it definitely works differently for pets than players, in that I took the Cu to Shame level 1 to hunt earth eles and mud pies to gain Wrestling, logged off with wrestling at 70. Anyways the Cu was successfully discording Earth eles which have a bard difficulty of 60 and cu only had 20 discord skill. Could not do that as a player. Wondering if pets have 120 music skill as a base or something.
Also I saw in an older thread about discord someone mentioned seeing "Zzzz" on the mobs. I use EC and also saw it several times. Looks just like mystic sleep spell, only lasts 1-2 seconds. Didn't seem to have any effect on the mobs and my best guess is that this is showing me the pet attempted discord and failed. Not sure if it shows using CC client.
Regarding aura of nausea; I don't have any figures regarding how much it debuffs the mobs, but I can tell you it works very well. It costs 100 mana, but IMO it's worth every point. Pet frequently uses it, typcially 1-2 times near the start of a battle. In EC it does a graphic like one of the spells spellbinders cast that has black smoke and the image of a person, so it's very obvious when pet uses it. Anyways, it looks awesome and it's very effective. At one point the Cu was surrounded by around 3 earth eles, 2 mud pies, and a scorp and after nausea went off they were all dead within a couple seconds.
Conclusion: It's early and the Cu's skills are pretty low right now, logged off with discord at 30, wrestling/tactics/anatomy around 70. Definitely a viable build and potentially a very good build. Cu has just over 700 mana and goes through it quickly like most Cu's do, but often has enough at the start of a fight to use aura and then attempts discord. Could be very good at champ spawns. I'll update again once skills are higher.