I’ve raised the question 2y ago ICRC-1 multiple token ledgers inside one canister
@mariop came with a good idea - You don’t need to make another standard. Candid supports adding new fields to icrc1. Just don’t think of it like you are creating a new standard it will make it harder to understand, but more like adding a field token_id to functions. If someone doesn’t specify it - it works with the main token unless specified.
For example: there is no such thing as mtls1_mint and mtls1_burn, not needed. Transferring from/to the minter account makes it possible.
mtls1_multi_transfer - there is already icrc4 batch.
If you are going to redesign the whole ledger system or even add a token id field, just to get multiple tokens at this point, nobody will support it for years. Probably not worth doing at all. Our tech removes the need to have multi-token ledgers for a lot of needs, so you will be trying to solve problems that have already been solved.
You could definitely create your own ecosystem with completely different solutions, which may be better, but unless everyone drops everything they’ve been working on to switch to it, you will create yourself a lot more problems than you are solving.