Lets put it this way: the biggest fun in vanilla WOW comes from playing on a fresh server right from the beginning, and to be part of the "rush" and the initial "shaping" of a server.
That's the reason why you'll see huge population drops after a while and also the reason why people were constantly begging blizzard for new servers during 2005-2006.
The ranking is done, people are BiS geared, sitting on a mountain of gold controlling the economy, low level pvp brackets are controlled by rich twinks you don't stand a chance against, open world is ganked and griefed 24/7 by bored 60s.
I'd say take a break and wait for the Crestfall release as it will be the superior server anyway. I was in the same boat, and I figured that my only choice would be to play a second-rate healslut on elysium or to just wait for the next project that will eventually come along.
regards and GL