It really wouldn't have to change token prices at all. The token is really just $15 for X gold. Just adjust the cost of services based upon that. Let tokens control their own cost and then adjust the other services along those lines.They just need to make the tokens able to be used on all the stuff they sell in the store as well. Granted, it would cause token prices to skyrocket, but still, the only way I'm buying Legion any time soon is if I can buy it with gold. And there's tons of pets and mounts I'd love to have.
If a token is 60,000 gold, server transfer would be 100,000 (20,000 gold = $5 in this example).
Tokens should only be based on subscriptions. Everything else adjust to that.