It's dissapointing that such a great game doesn't have both Magic Mirror & Transmog system, though I think that we will get smth like DoS2 Magic Mirror soon enough.
Hopefully they do add Transmog because it sucks looking like a random dumpster clown instead of a badass adventurer. Not to mention that there is no point in having so many cosmetically unique items which serve no gameplay purpose, such as Lae'zel's boots, Karlach's clothes/boots, Minthara's gloves, Astarion's clothes etc... very beautifully crafted pieces, but they're useless in actual gameplay. Would love to preserve some character's origin appearances and hide some pieces for others.
For my own character I'd love to keep the Drow armor since she's a Drow, but instead I gotta look like a clown Paladin wannabe despite being a stealth Ranger

As for changing our appearance, another person on the forums mentioned that the feature is confirmed to be in the works by a dev member, so could probably be one of the upcoming features with Patch #2.