A Reddit survey is not an accurate guide of true population numbers or race balance.
If lots of players leave Shazzarah for Firemaw then the queues everybody was fearing on Shaz will now appear on Firemaw instead. As for balance if Alliance is heavily outnumbered, which I doubt, then moving just creates s bigger problem for the Alliance that stay. And for all we know we could go to Firemaw and end up being outnumbered there.
I agree with reserving a name on both servers, but let's not immediately abandon Shaz on the basis of a survey filled in by a small number of the total players.
Queues will be everywhere, that's not what I'm bothered about. The blatant Horde bias on Shazzrah does concern me however and the consensus is that it will be a toxic ****-hole.
Any new player that's joining will probably lean towards Firemaw given the amount of communication we've had from Blizzard. 29k responses on the Reddit survey is small in the grand scheme of things, but it gives you a decent indication of where people will be going and who you'll be playing with.
Feel free to look at the live results yourself - https://docs.google.com/spreadsheet...id1Pf3MzUbYULs-kzYlL2lMrRY/edit#gid=858540573