Overall great idea and proposal - I am going to suggest going about this a slightly different way though, which should achieve a similar result - tons of cards being burned!
Ever since the success of our 5 year anniversary DEC burning event back in May, I have wanted to do something like that again, and I think this is a perfect opportunity for that. So I propose that Splinterlands does another burning event that works pretty much exactly the same way as the last one except that players must burn cards instead of DEC.
The company can provide titles and other prizes like we did last time, but we don't have as much available now to give out so I would propose to the DAO that some of the RW packs that are being given to it as part of the daily burn be made available as prizes for this promotion.
I expect that the DAO will receive something around 150k RW packs in total from the daily burns, so I'm thinking that the proposal could be for the DAO to allocate 50k of those packs to this event as the bulk of the prizes. I can work out the details and math for the amount and type of cards burned that lead to a chance of winning a prize, but I expect it will be similar to what you've proposed here.
Also, from an implementation perspective, if the packs set aside for the DAO are used then we're not under as much of a time crunch, and also by simply doing the burn event again we can re-use all of that code so it should be much quicker and easier to implement than if we do something that works differently.
Let me know your thoughts. If you like my idea and want to edit this proposal, reach out on Discord and I am happy to help you with that, or if you prefer to keep your proposal that is fine as well.
RE: Burn cards for Rift Watchers packs (EDITED TO MATT'S PROPOSAL for a burn event)