For what it's worth, I have very few issues on Draenor, and there's another 5 boxer on the Horde side, don't know if they post here or not. Draenor is one of the older servers, there's tons of 80's, but leveling you can very often have a zone to yourself, except for some bots maybe. I was getting herbs in Outlands on Saturday to level an alchemist, and I saw ONE person the entire time, in Shattrath (okay, it being the last night of the HH also helped, heh).

On Alliance, chat is VERY active on Draenor, and the AH is very established and you can generally find anything you need, and our prices are about average. The ToC patterns and recipes are pricey, but everything else is reasonable. Farming is more work, for ore, because of so many people out looking for it.

I don't know the server population numbers, but it seems to me we're pretty balanced - PvP wise, it's pretty equal, Horde controls Wintergrasp as much as Alliance does.