How about adding more with this as the template: - Ami stays green, while Mami turns silver (CycloneMetal) - Ami green, Mami blue (CycloneTrigger) - Ami red, Mami silver (HeatMetal) - Ami red, Mami blue (HeatTrigger) - Ami red, Mami black (HeatJoker) - Ami yellow, Mami blue (LunaTrigger) - Ami yellow, Mami black (LunaJoker), and/or - Ami yellow, Mami silver (LunaMetal)
Add another post with Ami wearing white, with Mami wearing black (FangJoker). With the same pigtails but with Ami's bangs (since FangJoker's dominant personality is Philip).
Or if you let the center splitter open, with the bangs from both Futami Twins, and the outfit based on the letter X. That way, you can post Ami and Mami as CycloneJoker Xtreme.
Ami Futami = Philip. Ami Futami's ponytail is tied to the right, which also explains why she forms W-tan's right half. Philip's real name is Raito Sonozaki and when "Raito" is katakanized it shares the same meaning as "right", hence forming W's right half.
Mami Futami = Shotaro Hidari. Mami Futami's ponytail is tied to the left, which also explains why she forms W-tan's left half. Shotaro Hidari's surname "Hidari" has the kanji that means "left", hence forming W's left half.