It mentions half of your new roles. Twins was one of the random roles I thought about adding once.
Scroll down for common roles [en.wikipedia.org]
It is a bit different from what you have though...
Sibling pairs typically consist of one Mafia and one Innocent; if one dies, both die.
*Looks through the list*
Wow. This is packed with tons of interesting stuff. I wish I've known of this sooner. Actually (and I'm not lying here) I've thought of all of these roles on my own. I originally intended to call the pimp and the flasher a prostitute and a molester (with similar powers) but Hark convinced me that it might offend some players.
When I first came up with the twin concept my first thought was to link them so if one goes, they both do but I considered that to be unfair since they only get to kill collectively once per night and sharing one life would increase the likelihood of them dying by 100%. Having them constantly protecting each other sounded like a nice trade for the whole communal killing thing.
And Hak. I agree. Those twins sure look creepy.