I have an idea how to improve NFT and jettons: Authorized-Controllable Tokens.

For example, consider someone who needs to transfer NFT to other person at specified time. First person would request timer to schedule message. Then he needs to allow this message to transfer NFT; he could transfer NFT to timer account first but then (1) NFT wouldn't be visible on the first account, (2) in case of some bugs NFT will remain on timer account forever, (3) someone could request another message transferring NFT from timer smart-contract to her first.

So I propose to create Authorized-Controllable Tokens. Owner of some assets sends an authorization message (contanining address of controlled tokens, allowed operations and so on) to smart-contract. At needed time smart-contract sends a message with Merkle proof of its authorization to NFT/jetton wallet contract, token checks the proof and performs the requested operation.

If owner wishes to revoke control on his token, he could send a message revoke_authorizations_before to his token (not to authorized contract, because that would need to increase Merkle proof to prove that there were no deauthorize messages).