Yay I love Buster! Mostly the suit design though, the character feels underutilized.

A manga about his younger years would be cool.

My assumption is it is either that or the illustration that was revealed is a front and it is actually gonna be a 4-panel manga of him and Sora and their day-to-day non Sword Of Logos life drawn by the Pop Team Epic guy. :lolol

A Kamen Rider Buster manga? I've never actually read one of those before, but this sounds interesting. I'm all for side stories and backstories, and this'll probably be one of those.

Wonder when we'll see Kento make a comeback as Calibur? It'd be nice for Mei to become the next Espada.

Kento becoming Calibur for a brief time and/or getting a "Espada Shin" form is more likely than Mei ever becoming a rider. She's being set up as another "Sophia" with the white book she has and the key to the Northern Base. They could pull the same thing they did with W and have her transform as a rider for a gag, but I doubt it.

There were fan-theories that she becomes Kamen Rider Flint because she's the "Flint that sharpens the swordsmen", but we'll just have to see. Reika has more likelihood of becoming a Kamen Rider than Mei, on pure personality alone.

Yup.
And Reika has "Shin" in her name meaning "God" somehow. Every character with "shin" or "kami" in their name so far became riders. While Mei don't have it.

Although I also strongly doubt Mei will become a rider, I think it’s worth pointing out that it wouldn’t be the first that a hyperactive comedy relief heroine became a Kamen Rider, and I don’t think anyone would have predicted it for Poppy either.

To add to this, kami depending on the kanji can be either paper or hair, though considering this season is not about hair stylists saving the world one snip at a time we can limit the wordplay reference to diety and paper probably.

Except Poppy was revealed as a Bugster since the first episode, so her chances have never been low.

Except most Bugsters were villians, so I don't think that her chances as a rider were all that high.