A loyalty/veteran program would be a good idea, but god damn the OP really needs to take some sort of business class or something. Discounts on the sub cost up to and including free? Wow. That's just an awful business decision.
I certainly WOULD like to see some vet rewards... That said, remember the backlash against the annual pass? Basically a vet reward test pilot, and so many people whined about how they wanted to stop paying Blizzard but still keep the rewards. I mean, lol. Just silly.