I think the eventual new character models are what still keeps me playing. If they were introduced as a cash shop only feature I think it would make me stop playing the game for good after 7 years. I can justify the monthly fee because I find the time spent ingame worth the 15euros a month. However, having to pay for a fee on top of that to enjoy the character I'm playing (with the new models around I would imagine the old ones would look preety awful ) is a kind of expence I cannot justify, especialy now that money is realy short for me. I find it a little upsetting that I cannot own the mounts or pets in the blizz store, but I can play without them. Dont think I count still play the old models with the new around.
Just my opinion, tho.