I'd love that too or a way to replace the appearance of gear with what you prefer (like in FFXIV online).
Even if we have many crafting motifs and an huge number of combinations, we are full of copycat characters with Molag Kena for example.
I never liked the look of monster masks and shoulders.
At least being able to show two shoulders can be an idea, but I would prefer all the time a way to replace the look of a piece with what I like.
The single shoulder is probably because of the look of Mercenary gear, that it was designed first to be the look of Undaunted sets but implemented one year after as Mercenary motif.
I just want the option to use my OWN armor set as if it were a costume - Running stam sorc I'm constantly looking at my fugly purple daedric bound armor instead of the awesome set I crafted.
I'd really just like a way to hide the bound armor or select "Own gear" as my costume to overwrite it.