I saw a few suggested posts talk about this, but they're missing a few things that I'd like to suggest as well. It's one of the few things I miss from Second Life, where emotes, toys, and other things weren't tied to only one avatar, but to your account as a whole, allowing you to use them on any avatar.

I would love to see the separation of "baked in" toys and emotes from avatars, and have them put into their own uploads instead. Could potentially also reduce avatar sizes indirectly as well. Giving us an inventory system would also allow us to use these things outside of avatars we've uploaded. Sure, there would be some things that you probably want hard packaged in a specific avatar, but it would be nice to have.

Want a boombox that plays music? Instead of bundling it with your avatar, just upload it, and bring it out.

Have a dance/emote you like on your personal avatar, but want to do it on an avatar you didn't upload? Now you can.

Want a flashlight but your favorite avatar doesn't have one? Just buy one off of Gumroad/BOOTH, and now you always have a flashlight handy, no matter what avatar you use.

Bought some camera filters/controls for recording, but the avatar you want to use wasn't uploaded by you? Not to worry, just toss it in your inventory upload.

And of course, have Inventory uploads work under the shield system. This should go without saying.