Inbox and outbox are lists **for your followers to find you** not for you to find the content you want.

If you want to use fancy new algo relays, or look at a global feed from specific relays, or backup your content to other relays, or use NIP-29 group chats, or always send stuff to other relays in case you get rug pulled by the current ones... none of those should be in your inbox and outbox lists. None.