My problem with the XP disabler is that it exists at all.
Paying to level more slowly, as an antidote to the stupidly-fast levelling "experience" the ever-more-impatient new players want? Not me, no sirree! No other MMO I have played requires you to pay extra money to spend longer in-game, its a brilliantly cynical marketing ploy.
I suppose such gimmicks as these may be inevitable, but they still siphon off some of the fun for me. Eventually the cons are going to outweigh the pros, I think. Until then, I shall continue to enjoy the game as much as possible. After all, look on the bright side - I played for 2-3 hours last night with no crashes! Yay!
The best suggestion here is perhaps to disable the rested xp boost with a toggle. After all, one was provided for the forced-emote haters. Not just for the subbers though, for everyone. You're asking to get price-gouged if you suggest every provision should come with a price tag, some things should exist simply because they make the game more playable and more likely to retain players.