Rakan and Xayah have so many skin themes to explore, and here are some of mine
Academy Xayah and Rakan, basically those young lovers in school, Rakan being the popular guy adored by everyone and Xayah being that outcast-ish girl who for some reason takes no interest in Academy Rakan
Groom Rakan and Bride Xayah, self explanatory
Tango Rakan and Xayah, something similar to tango Eve and TF
Festival Prince Rakan and Festival Princess Xayah, a festival skin would fit Rakan more than Xayah though
Leave any more skin ideas if you gots any, kuz I bet there are so much more skin themes they could have