I've only completed TV KR Series of Heisei + Reiwa except Ghost.
My favs are: W, OOO, Drive.
Before getting to the topic, this is my opinion to most of KR series. Sorry for the bad english, but here we go.
-Heisei Riders:
In the later of Heisei Era, there are plenty of KR concept and story that is badly writen. So many uninteresting characters. So many weird developments that are not thought before they decided to go with the show, that the show itself don't know what is the big message they wanted to convey. At least that's what it felt to me.
It is a coincidence that my fav 3 KR has this certain "aspect" they shared together in the TV series.
-Reiwa Riders:
They are very badly written. Saber came from the same writer as Ghost, and his reference of rider item is weirdly unappealing. Storybook and Historical People. Like, it's better to make reference of something both rider fans and normal people know genericly. Btw, the Saber x Zenkaiger movie, it's bad written.
About Zero One, way better than Saber, but the side characters are also not that interesting. Why Aruto let Gai off so much just to get another Zero-One vs Thouser episodes. And... for those who don't know, Real X Time Movie referenced a lot of things that Evangelion referenced, it made me laugh so much on how they decided to use those religious things in a Kamen Rider. Well, the OTHERS Movie is just pure bad written and directed just to promote new toys and cash grab because Zero One seems to be pretty popular.
-Why Revice is a KR we've been waiting for:
Early episodes of Revice acting is not that good, but it has interesting story, concept, and characters.
The story connects with almost no filler episodes, why? Because the characters always develop. They think, they act, they reflect, they tried to be better.
You can't just be Kamen Rider with henshin item, you need brave and resolution so the Demon won't get the best of you. So far, every riders had development before they henshin'ed for the first time.
It breaks the "2 episode filler episode" formula, and inputted interesting aspects each episodes. Well, Saber and Zero One tried, but I think they did it poorly.
It has mystery and suspense, but understandable enough. Who you think isn't important, could be important.
It has various villains, with one as just a b4st4rd and still is. We at least know who will we hate after that guy became the current main villain.
-Vice is the best moodmaker you could ask:
It has boke and tsukkomi to wake the viewers from boredom. Having someone to comment on someone else is just the good way to make people not bored.
Vice is just a b4st4rd at first, but you will see how he will grow along Ikki.
He often do 4th wall break, aka interacting with the viewers. I thought it will be weird, but it turned out pretty amusing each time.
-About Revi and Vice in eps 48 of KR Saber:
I think this is made when they have no time. Vice's setting is not fixed yet, and they took the eps anyway. I mean, Vice seems like he wanted to eat the monster, right? Meanwhile in KR Revice show, I never saw him stating he wanted to eat the monsters. The editor of KR Saber eps 48 also took wrong order of Blades and his love interest reactions to Revice's henshin. It's sad how clear Saber has not been produced well enough...
