PW : Shield is still there as Shadow. Tho levelling as shadow is a painful joke atm (it wasn't before but then they decided to nerf everything that was fun about the spec).
Saying that perma Shadowform is the same as perma cat form is ridiculous. You're a little purple at 0 insanity, going darker the more insanity you have. You'll be able to see your transmog just fine.
They could have given us a glyph that makes shadowform at 0 insanity basically non existent but then again they could have also made a glyph that reduced/increased the amount of tentacles, but they didn't.