There is a new supplementary book in the works for supers system ICONS -- The Super Villain Handbook (tentative) by Fainting Goat Games. The book is still in development and Fainting Goat Games are actively seeking feedback on the material over at the book's Facebook group. There you can find all sorts of information and preview material.
The Super Villain Handbook will feature 40 different super villain archetypes. Depending on the version of the book (standard or deluxe) the archetypes will also feature either just a general stat block or fully developed villain, art and all. One good side to these villains is that they will be apart of the public domain. While The Super Villain Handbook is being written for Steve Kenson's ICONS, there may be a version for the Supers! RPG as well.
So, once again, if you would like to know more, see more, and provide feedback to the developers be sure to check out their Facebook group.