An excellent concept Vogar Eol.
The layering that you spoke of makes sense, and it is realistic. Knights were not naked under all that plate armor, does the word chaffing come to mind.

Quilted cotton was worn under chainmail for good reasons; it provided blunt protection that chainmail is weak against, and made penetrating wounds travel farther before they drew blood, besides just keeping down chaffing. As for your head, well if you don’t want your hair hopelessly entangled in your chain coif, you better wear something.

Now some races may go for the bald look to prevent this minor problem, but an elf, never.

Leather doublets were worn under a metal cuirass, often with a fine silk shirt beneath that, to show off your elven good looks, taste, and wealth.
The resistances you listed suit the materials you assigned them to well. As for how much, either 5% or 10% would seem reasonable. I guess the decision would depend on the availability of resistances for enchantments in the upcoming patch.
I think this would work well with the upcoming craft system. It would encourage crafting in various materials, and crafting in general. Not to mention the fine fashion statement you make with your equipment, something that we elves are prone to do.
So, let me propose a toast, three cheers for the dwarfs idea, may his ale mug be ever full.
(mumbles to himself) “Why didn’t I think of that?â€