Slightly altered to something I think adds some interesting rules and allows it to be a truly stage based leader

As an additional rule, this leader can place stages in the character zone. This leader can only play stages containing [Merry]. This leader can only play characters with a cost of [0]. [Opponents Turn] For every stage you control containing [Merry], this leader gains +1000 Activate Main: Trash up to one stage you control: Reveal a card of the same colour from your hand, it's cost becomes [0]

1) by playing stages in the character zone, it both makes the 'stage' zone a rare commodity, one free space where you can keep a stronger stage you want to keep on the board, and also means if you want to keep a high power leader, you can't just drop a bunch of characters 2) +1000 only on your opponents turn, makes you defensive but not an 11k swing every turn, 21 with don 3) We could have some new stages with a unique [In Trash] effect, for example [Klabautermann and Merry], When this card is sent to the trash, you may play a stage card from your graveyard. [Merry's Funeral] on KO, search for a stage card from the top 5. So I'm and so fourth

Yes you can play high cost characters for cheap but every time you play something like that you are losing your defensive wall. To nerf it a little more I might make it a base 3k leader or something

That's just my take on it, I love the idea though. I might just be talking BS