At least lately all the new cosmetics are via vendors (including the ones from this pack), so you just destroy them when not in use to free space and reclaim them again when needed.
That would be ideal.. Like you can destroy your Salt Marsh Cosmetics, and IOD Cosmetics.. etc.. and you can just go back to that vendor to get the item back.
That would be an ideal route to go. It would free up some space. They could make a vendor that has all the cosmetics on it, and if your flagged , as in you bough that expansion, then you would be able to get the cosmetic from the vendor any time you wanted. Or if you have bought it from the DDO some cosmetic.. even it would be on this vendor. If you havent purchased it, it wont let you have access to it, until you buy it from the DDO store.
That would be an idea just for cosmetics.. Now for gear, that is a different story. I have like 25 or more character slots.. 4 of them I used for playing characters, all of the rest are mules named like Heroicsx OnetoFive heroicsxx SixtoTen etc.. its like that up to epics, and its done the same way. Then mules for Sharn and Ravenloft named loot, Mule for IOD and Saltmarsh Loot, Feywild Mule..
All that logging on and out, in and out.. Waiting to log out... take a minute sometimes.. or more.
If they just got rid of TR cache, get rid of BTC items, make the shared bank default , really huge like 1000 slots.. We can make tabs.. Then when they release new content, getting more slots comes with the expansion or whatever. They have to stop releasing items into the game, and not giving us space for it.. Then charge us for more space.. So in essence they charge you twice. One for content, and two for having to buy space to put the items.
Its something they really need to work on.