I used to do a lot of BG - really enjoyed it. The thing I really enjoyed was a close BG, not an honour farm or quick marks - not much fun in that not much of a 'game' really (usually AV). I also didnt like losing the same BG over and over again (usually AB).

A BG where I didnt know who was going to win was great, certainly not a foregone conclusion after 5 mins.

I presume it would be too difficult to try and balance battlegroups and stop the 'which is the best horde/ally BG for pvp' questions?

Horde dominant in 1 BG, Ally in another - put them together rather than let them dominate all the time and the otherside lose.