Not sure if it's possible, but:
A pack that lets you change your character's physical appearance to that of a different race, without changing racials. So you can take a Khajiit and make them looke Argonian if you want. You still have your Khajiit racials and everything. The same way you can flip between hairstyles or body/facial markings if you own the packs.
I noticed, when making a new character, that I could switch between races and all my sliders and color choices remained. So you can flip between them without looking too freakish, at least in character create.
The biggest flaw I can see with this is that the only two races that end up being created from that point on are Redguard for stam builds and High Elves for magicka. Then people would just make themselves look like the race they prefer. I mean, people kind of already do that, but it would make the problem much worse.
Edited by Cheveyo on January 21, 2018 10:16PM