Interesting additions to the lore. All of this (except maybe Demi-Princes) have been brought up before in past games or lore. The Slipstream finally gets some detail and it almost seems Mananauts are now.... "canon" to the lore (?) Probably the most interesting part of all this is the idea of "Demi-Princes" though.

http://www.elderscrollsonline.com/en-us/news/post/2015/10/19/loremasters-archive-the-maelstrom-arena---part-one

Imperial Mananauts were previously mentioned in the Arena Supermundus section of the PGE3, along with Alinor Sunbirds.

Yeah, the Mananauts, Demiprinces, etc. have been around for ages. This is just helping flesh them out.