Near as I can tell, if it says Ringmaster on the wing, it's legally a Ringmaster. I'm pretty sure there are at least 20 variants. Somebody should come up with a Ringmaster Flash Profile 600...
When Brotherhood of the Ring (BOTR) website was active, AFAIK, the rules for being a Ringmaster variant was utilizing the flying surface outlines of the Ringmaster (say S-1 or S-5 Junior). It did not have to follow the fuselage outline. Flying surfaces had the same basic proportions. Any deviation had to be approved by the BOTR to be considered an official variant. One such BOTR approved that deviated slightly by the wing shape was a swept wing Ringmaster.
Another kitted variation permitted was Sterling's flying man configuration.
I took the S-5 outlines and downsized them to half-A size, then used Keith Laumer's Gee Bee Z profile half-A plan fuselage, modified into the Gee Bee Z Ringmaster. Used poster foamboard as the major construction material. Except for the fuselage, it looks like a Ringmaster.
Purpose of the variant design event was strictly for fun. See how one could take say, a scale plane and Ringmasterize it. Doc Holliday made a Canard Ringmaster. One could use a variant in the annual Ringmaster Fly-A-Thon event.
To tell the truth, it makes me sad that the Flying Clown and Super Clown are not legal for flight counts on "Ringmaster Day", since they were all designed by the same guy, whose name I've forgotten. I'm not sure if he designed any models besides the RM's and Clowns, but I'd hope so.
Designer was Matt Kania. Matt not only designed the ones you mention, but also designed other non-Ringmaster planes: Sterling F-51 Mustang profile, Yak-9 profile and others, worked for PDQ, Sterling and Megow. He designed the S-1 Ringmaster, S-5 Ringmaster Jr., Super Ringmaster and Baby Ringmaster. However, I gather that perhaps not all Ringmasters were his.
Because he did more than Ringmasters, would deviate from the purpose of the Ringmaster events, IMO. I suppose if one could popularize a Matt Kania CL event, then his other CL designs could be included.