After looking around and considering various funding sites, I finally settled on Patreon because of the nature of The Outer Rim Project. Unlike most art books, this is not a one off. This is meant to be on going. I don't have an end in sight, and so I felt that Patreon best fit the needs and scope of the project.
Once complete, each art book will be available to whomever wishes to purchase it. However, the Patreon site will allow fans to directly engage in the development process, get cool perks like post cards, access to works in progress and behind the scenes, original or print art (some illustrations are done entirely on the computer, so no traditional "original" exists), coffee cups, and more as a way of saying "Thank You" for your support.
As an added bonus, fans from my Alien Suns Stellaris Mod will have access to new portraits before formal release, regardless of what level they've signed up for.