If you're a crowns player (like me) you probably agree that right now, the Ranked PVP payment system is pretty bad. You either pay by the game or the day, both of which are fairly short term. I think a pretty good idea would to add a permanent Ranked PVP (or pet derby) unlock. This would give you unlimited PVP and Derby access on all your wizards forever (without membership). I think a reasonable price for this would be maybe 5000-7500 crowns (10-15 dollars worth). Hopefully something like this is implemented so crowns players can really dive into PVP at their own pace.
Right now the server population is still growing with new members, that means more money rolling in. After Wizards crests the peak and membership is on the decline I can see them doing this. But it is a good idea.