I'm gonna change the 1st person legs mod to use the capes slot because it's too much of a hassle to mess with the rings slots. Do you have gloves on, do you have unlimited rings, do you have visible rings etc etc.
The tail slot has the extra advantage of solving the "tail clips with cape" problem! However, screenshots in the Hemingwey's Capes thread indicate his don't use it.
As far as I know tail slot will not display in 1st person though. Only a very limited number of slots are rendered when in 1st person. There's not much choice where to equip items, if you want them to be visible in 1st person.