1) The top 50 guilds by total achievement points make the list.
2) Only the top 500 characters in each guild that have played in the last 7 days are...
So it looks as if there are 3 parts to this. One is the alert in the Alerts panel (which the toggle affects), one is the hud system message, and one...
Sorry, no shared perks. However, I could see allowing your spouse to move items in the house and adding visual "tethering" effects, but that's about...