I was thinking there could be BTA chest earned in events like Crystal Cove. You could store only items from that event in them. Items could be added and removed from the chest.

Could store event crafting items in it as well.

Possibly BTC things could be shared to other toons in your account.

Be an easy way of finding the gear for that event.

I'm not sure about the storage limit, probably at least 40.

Maybar could have a Crypt.

Have something for Anniversary Party as well. Maybe a big Top Hat.