Here is different CL card burning idea instead of an event that the DAO could pay for. If it won't work that's fine but I just want to get it off my chest. Change the numbers, modify it, pick holes in it, whatever - it's for discussion purposes.
This is the simplified version/non crafting version:
Create a rare and epic wagon that requires burning CL cards and it drops a number of BCX of a permanently soulbound epic or rare card.
It costs & works the same way & is on the same schedule as the current wagon except it drops BCX instead of chances (capped at 1 max level card) & it requires that you burn a number of CL cards of the same element as the wagons are dropping.
So for the rare wagon let's say it would require burning 20 common CL cards or 10 rare CL cards.
And you set it so the burning slots "meet a minimum requirement or better" meaning that if someone has a 26 BCX common CL card & he wants to use it for this it still works or if he bunches together 23 BCX in 4 slots it still works.
For the epic wagon likewise you could require burning 20 rare CL cards of the same element or 10 epic CL cards of the same element.
You can keep this up for as long as needed until you burn the amount of CL cards you want out of the system and stop it if the player base grows and needs CL cards and/or if land accelerates in use and gold CL cards are needed for land.
I feel this leaves a lot of options open to play with to increase the amount of CL cards getting burned. You can change the numbers around. You can make it so that if you want a guaranteed GF all the cards you burn have to be GF. You can make a special ability just for these cards that requires legendaries to get burned to craft it onto the card. There are so many options to play with and you don't have to call it a wagon.
My 2 cents.