Honestly I was planning to use Foundation X as the reason why my guy is using a preexisting Rider gimmick. Foundation X is already known in canon to study the various Rider power sources (Gaia Memories, Medals, etc) so it would make a lot of sense if they used their research to create their own knock-off Rider. My only thing is I can't decide which gimmick to use. I've got an idea for a Shift Car/Signal Bike user called Kamen Rider Brake, but at the same time Astro Switches might be a fun choice and W happens to be my favorite Rider of all time (duh, look at my username) and so going with Gaia Memories also seems like an obvious choice.