You can sneak in heavy armour too. The Heavy Chitin set weighs about the same as a Steel set, but offers more protection. You could imagine it's still handy for an assassin.
It is, but only as part of the Dragonborn expansion pack. You can make Chitin armour for yourself, and also some Morag Tong assassins attack you, each wearing a Morag Tong variant of regular chitin armour.
Not on the regular game, if you really want to, get the game for PC. I'm sure they have a mod for it on the Skyrim Nexus or on Planet Elder Scrolls.
The Morag Tong (Forester's Guild) are a legally sanctioned, secretive guild of assassins that originated in Morrowind. They are said to have been founded by the daedric prince Mephala as a way to destroy enemies of the Chimer people using conspiracy and murder. Sometime during their past, the group splintered, creating another faction which is more well known, the Dark Brotherhood. Their 'legal status' in Morrowind gives them the authority to issue their agents with an official 'Writ of Execution' which the assassin will present to the authorities immediately after making their kill. This writ absolves the assassin of the murder, and he is set free. The order was said to have been dissolved when Morrowind was rendered uninhabitable due to the eruption of Red Mountain. However in Skyrim's expansion, Dragonborn, Morag Tong agents are encountered.
Morag Bellingham was born in 1948.
Morag Bellingham was created in 1988.
Morag - moshav - was created in 1983.
Shlomo Morag was born in 1926.
Shlomo Morag died in 1999.
Morag Siller is 5' 2".
Morag Sims is 5' 1".
Katie Morag was created in 1984.
Morag Fullarton has written: 'The tenant'