I haven't thought this through much but

This could make NIP-65 more useful as a global relay configuration standard that could configure proxy and aggregating relays with support for the inbox/outbox model

Disambiguate read/write values in kind 10002 relay tags:

aread - author reads from this relay

awrite - author writes to this relay

oread - others read from this relay (outbox)

owrite - others write to this relay (inbox)

So if I have a relay filter.nostr.wine that aggregates from nos.lol and relay.nostr.band and doesn't allow direct writes from unauthorized users, kind 10002 relays would be

nos.lol

owrite

relay.nostr.band

owrite

filter.nostr.wine

aread

If I also use filter.nostr.wine as a proxy relay that broadcasts to nos.lol and offchain.pub:

nos.lol

oread

owrite

relay.nostr.band

owrite

offchain.pub

oread

filter.nostr.wine

aread

awrite

And if as well as reading and writing to filter.nostr.wine I read and write to relay.damus.io in a standard inbox/outbox way:

relay.damus.io

aread

awrite

oread

owrite

nos.lol

oread

owrite

relay.nostr.band

owrite

offchain.pub

oread

filter.nostr.wine

aread

awrite

This way there's no need to put things which are by nature global configuration into client-specific settings

From a UX pov the configuration for each relay is relatively easy: do I read from this? do I write to this? do I want others to read from this? do I want others to write to this?

I feel the current NIP-65 overloading of read/write values with different author/other client behavior will create more problems

And I don't agree with the nudging of clients away from using NIP-65 for global configuration beyond inbox/outbox model:

"kind:10002 events should primarily be used to advertise the user's preferred relays to others. A user's own client may use other heuristics for selecting relays for fetching data."

Nostr is a constellation of compatible apps, it's helpful for the user that everything that is by nature global configuration is supported