Armor models specifically for tails might be too tall an order. It's probably a logistical nightmare trying to make sure every set is compatible with tails, but a good start would be a feature to hide the tails entirely. Something like /tuck and /untuck, the explanation being that the tails are tucked into armor, or otherwise hidden beneath it. It's just plain weird seeing robes, skirts, capes, or heavy armor in general have tails awkwardly jutting through them, especially when the clipping issues begin to ere on the severe side.