Mixed group ideas and mechanics

So, my situation is this:

I have a 70 Mage, my main, will likely always be. I have a 62 Priest and I plan on rolling a Death Knight when the expansion hits (I can transfer an abandoned toon to a new account to satisfy the unlock requirement).

That leaves two toons left that I need to level. I was thinking some combination of Warlock, balance Druid, or elemental Shaman, but can't decide which two. They all have various things that would benefit a caster-oriented group, in addition to various forms of crowd control.

Warlock has CoE, though it probably wouldn't be much use to a Druid or Shaman as it doesn't affect Nature spells, and only marginally the Priest if she's going to be mostly healing.
Shaman: Totems - 101 + SD/healing, 3% crit/hit, and 1% hit (Draenei racial).
Druid: Moonkin (5% crit)

I would probably take the Shaman buffs over Moonkin anyday, though managing totems in a mixed group kind of concerns me. It's one more thing to do and keep track every time I move (though I read totems are being condensed in WotLK which should make it less of a hassle).

The Warlock is tempting. Lots of DoTs for big pulls (+ SW : P if I can pull the Priest off healing for a bit). Soulstone, lots of different forms of crowd control... but Moonkin aura and Mark of the Wild + Shaman buffs I would think would be pretty insane.

Gah! It hurts my head.

I know mixed groups are a hassle and it'd be easier to roll more Mages, but I get overly ambitious like this. I've been boxing since EQ but gave it up when WoW came out as I tried to apply the same methods I used in a game with entirely different mechanics and found it very tedious, but now that I've found this site, the macros, software, addons, and everything else, I've become hooked again. I just can't decide what classes to roll! :(

EDIT: And now I see that Wrath of Air was changed to 5% spell haste. Ugh.