Hm, why just limit yourself with colors-pallet.
We can advance further and convert SEED phrase into music.
I have just used
Music Sheet Cipher and converted the following SEED (search where universe puzzle search doctor dumb holiday patch wheel begin detect) - don't use it! - into music notations.
You must have good musical knowledge to understand it. Does the musical sheet contains all seed words and does not include non-seed words?
Because if you hide your seed words, mix them with non-seed words, you will have problems to find whatrl words are from your seed.
It is better if the sheet only contains seed words but what will happen if with this large piece of paper, you will have more risk to see it gets wet, damages by physical threats. I could be wrong but a smaller piece of paper is better for me to store my seed. It is more easily to backup, storage safely and recover in future.