[Switchblade]

Showa Kamen Rider is very episodic by nature. Some shows, like early V3, have a lot of two-parters, but there's rarely any form of ongoing plot arc. It's usually just done-in-ones with the only real changes being when new cast members arrive or leave (usually a general or the largely throwaway Rider Girls). It's not necessarily bad if you just want a simple action story, but there aren't a ton of options if you're watching the shows for character development or ongoing storylines.

That said, if you want some shows with longer storylines:

- V3's Riderman arc isn't terribly complex, but does feature some character growth and development as Joji learns the truth about Destron and slowly comes around to fight alongside Shiro. It's still fairly shallow compared to modern shows, though.

- X has the blueprint arc, where he spends several episodes competing with GOD's monsters (including the infamous Starfish Hitler) to find the scattered instructions for a super weapon.

- Stronger's Delza Army arc is relatively serialized and has some good character interaction moments between the various army generals.

- Black RX has a few multi-episode story arcs, most notably the episodes where Kotaro goes to the Demon World and gets his Robo and Bio Rider forms.