Team setup discussion - add warlock and/or driud to pally/shammie team for WotLK?

With the new WotLK talent tree for balance druids, they're starting to look increasingly appealing. I'm not sure if the spelldmg-part of the improved moonkin aura will stack with ToW, but even if it doesn't, a balance druid would still be a nice addition. Warlocks also seem nice, with CoE affecting nature spells also.

Druid

1) Earth and Moon:13 % spell damage increase to target
2) Crit aura (no need to spend talent points in oath)
3) CC (with root working indoors)
4) MotW

Warlock

1) CoE: 10% spell dmg increase to target (doesn't stack with earth and moon)
2) Blood pact
3) Banish allows for a wide range of CC In combination with shaman hex
4) Wide range of debuffs

Totems

In order to estimate to impact of swapping one or more shaman we have to take a look at totems and totem stacking. I've listed the totems by element and priority in a tank/healer/dps group:

Earth

1) Tremor
2) Strength of Earth
3) Stoneskin
4) Earthbind (stacks?)
5) Stoneclaw (stacks - situational)

Water

1) Healing/mana* (stacks currently but probably wont in live)
2) Mana spring** (resto only - situational)
3) Fire resist (situational)
4) Poison cleanse (situational)
5) Disease cleanse (situational)

Fire

1) ToW
2) Flametongue
3) Searing (stacks)
4) Magma (stacks - situational)
5) Fire nova (stacks - situational)
6) Frost resist (situational)

Air

1) Wrath of Air
2) WIndfury (not sure on usefullness of this one - might work well for paladin aggro generation post-WotLK)
3) Grounding (stacks)
4) Nature resist (situational)

Removing 1 shaman

By removing 1 shaman, we of course remove one totem per school. Going from 4 to 3 shaman, would result in the loss of:

1 grounding totem
1 searing totem
1 earthbind
(I haven't mentioned mana/health totems since I assume it won't stack)

And in the gain of either:

1) 13% spell damage or 10% spell damage
2) MotW or blood pact
3) Root (same targets as hex though) or banish

There are of course several other advantages, but these are the key reasons for the class-switch. I haven't mentioned crit% since Elemental oath can also supply this.

Removing 2 shaman

By removing 2 shaman, we remove 2 totem per school. Going from 4 to 2 shaman results in the loss of:

2 grounding totems
2 searing totem
1 earthbind totem
1 stoneskin totem (can be replaced by single-target attack power debuff from warlock)
(I haven't mentioned mana/health totems since I assume it won't stack)

And the gain of:

1) +13% spelldamage to target
2) MotW
3) Bloodpact
4) Banish
5) Root (same targets as hex though)

Discussion

So the question remains - what is the better setup, when the options are:

Tank: Paladin
Healer: Shaman
DPS1: Shaman
DPS2: Druid/Lock/Shaman
DPS3: Druid/Lock/Shaman

Now, if you've read all the way down to here, feel free to air your preferences and reasons for/against exchange of one or more classes. Would you prefer keeping 4 shaman? Or switching just one? Or switch two? Maybe add another class?

I went with druid, but then again, I had priests.