How can I use nostr to post jobs, eg in a more structured manner than a text note?

I'm not sure if using an existing nip would be wise? (eg nip-99 is the closest to being suitable that I can see).

I don't know enough about relays yet, do the different relay implementations generally follow a similar subset of nips, making it kind of important that a nip gets included by most of the relays, for it to get adopted widely?

So there is a bit of lag between a new nip and the relays using it, if indeed they ever choose to?