You know I just noticed something.
Kota's sister was actually Sailor Mercury from PGSM. The resemblance is damn precise that it can't be false.
First Sailor Moon's multiple appearances in the Rider franchise (Sawai Miyuu guest starring the Kamen Rider W's portion of the Decade/W Movie Taisen, and Sawai Miyuu's latest appearance in Kamen Rider Wizard's final episodes), now we have Sailor Mercury entering the Rider franchise.
I knew, but I'd also looked up the cast.
Maria Cranberry from W's Gaia Memories of Fate was Queen Beryl.
Nomura Shizuka from Kiva was Luna (human form).
Snowgel (voice) and Hiso (voice) in Magiranger and Gekiranger were Luna (voice).
Ibuki was Mamoru/Endymion. He was also Nakazato Hiroshi in episode 15 of Kyoryuger.
Someone in episode 45 of Dekaranger was Jadeite.
Gamel was Nephrite. He was also someone in Kabuto, but EN wiki linked to JP wiki, and I can only read the name of the series.
Someone in Blade (again, can't read the JP wiki) was Kunzite. He was also someone in episodes 32 and 37 of OOO.
Shizuka from GARO was Mio Kuroki.
Kamen Rider 1 (The First/The Next) was Motoki.
Someone in episodes 11-12 of Den-O was Minako's Manager. He was als--- wait?! FUEKI was Minako's Manager?!?!?! I totally didn't catch that!!
So, yeah, a lot of the PGSM cast have gone on to do other Toku roles, and a lot of them in KR. There's probably more, but I was just checking the cast on Wikipedia, and most of the links were to EN wikipedia, which rarely has a lot of info on toku actors.