I would say that adding the master key fingerprint (mainly seen in the coldcard, recently also added to bitbox) would be a great addition especially as it can help people to know whether they are on the right wallet without relying on labels that have way too many dependencies, and is literally just a short id mathematically linked to the wallet. Even better, a passphrase user can also use this to confirm they are correct on a wallet that might not yet have got any coins in it.
Keypoint is that not having the mfp doesn’t gurt but having it makes a recovery a bit easier when it doesn’t go well.
or just write down the first address of the first Bitcoin account…?
I get where you’re coming from but for the average user a “master fingerprint” is just the seventeenth completely new thing they have encountered today and they won’t have any idea whatsoever as to what to do with it.
Writing down the address of the first btc account isn’t great especially due to multiple bitcoin types and most wallets making past addresses not easily viewable (also accounts)
The mfp is short and could be used universally and easily if ppl were to adopt it.
It should be accessible that even a person panicking about their coins having “vanished” noting it well enough.
Regarding what to do. In future revisions you could add a field for the mfp on the recov sheet and especially for passphrase users make a note in suite to note down the mfp.