Go to a battlegroup where alliance out number horde by vast ammounts. Simple reason is for queue times being next to none, but try and pick a server with a healthy horde population from that battlegroup.

I'm staying on Stormrage tbh, I enjoy 3boxing with a friend who 2boxes and we PvE mainly. I've almost given up on levelling more groups of alts simply due to time issues atm. And I'm enjoying PvP on my 68 warrior without the aditional toons... so I'll stick to that for now at least. I'd probably roll a trio to stop by and say hi to anyone who's online though and get some lvls in while rested...