Not all teams are necessarily PvE viable, particularly for heroics.

I believe rogues have some avoidance skills, but the cooldowns are not short.
You have Evasion for physical type attacks.
You have Cloak of Shadows for most spell type attacks.
You can fight from the rear arc, which negates a lot of cleave type attacks.

Still, everyone (except the druid) will be in melee range.
Spam your Wildgrowth, and possibly spread some HOTs around.



For pvp, have the DK sit down.
And type /AFK.

On my PvE carebear server, I've done that from time to time.
Naturally, with a flagged solo toon.
Doesn't always work, but can be fun at times.



Rested is definitely quite nice.
If you can though, focus on one group that is very PvE viable.
Get a bunch of heirlooms, which can then be traded down to other groups.

My plate classes were more than happy to use Cloth shoulders and chest heirlooms.
The experience bonus is worth it.
And the lack of armor/stats is pretty meaningless, when you have 5x classes killing things.