It would be really amazing if users could store the stage parameters for avatars they have favorited or are currently using (or it can be stored in a secondary local cache that can be cleared). This would essentially a be a menu beside the Expression menu that would allow users to store all of the favorite configurations of any avatar 3.0 avatars you own. This way, you can completely customize your avatar and load that customization on the fly without having to set it up all over again. It could also load whatever outfit they had selected previously when they change back into the avatar, leave, or change worlds until they choose to not wear any of them.
If necessary, in the Params object, users can choose which values are not allowed to be saved (so stage parameters part of a larger sequence don't cause problems).