Ryugen, Zangetsu, Gaim, Baron and Gridon are gonna survive at least until the flashforward war bit.

After thinking about it for a while,maybe Gridon will survive.But,will it be the same person behind the helmet of Gridon? We know they wouldn't kill off the actors playing the main four,but I just think Gridon doesn't have that kind of role.Sure he's helping Baron,but as a lackey.Not as a main character.So maybe down the line the guy using Gridon now dies,and someone else takes his place.(I mean it's not unheard of.There were multiple different Ixa,Births,and Kaixa)

Your arguments are valid and I agree. But at the same time, although a cliche of the genre, Micchy's first venture as a Rider is supposed to be badass and cool and sell us the character so we go buy the toys. Micchy's first venture in reality involved him being useless, getting his ass kicked and only made me buy Baron toys instead. Maybe that is the point.

And this war could happen pretty much anytime. Nobody said that its going to happen in the 30s or 40s

Thats going to be difficult since the drivers are locked to a persons dna.

The drivers are,yeah.What if,just saying,Gridon gets killed and Baron takes his Lock seed back.Or maybe someone takes the lock seed for themselves.The drivers are DNA based,but are the lock seeds? So far it seems the only thing the seeds record are win loss records.Maybe the lock seeds grow in strength with more wins.

I dont think people using the same lock seed will have the exact same design. Sure the Armor will be the same but the rest of the Suit probably wont be.

But that only changes the fruit armour. The rider design doesn't change with the lock seed. Baron's face is unique to Baron. Considering this episode just debuted Gaim's third armour, I don't see how you don't notice this.

That's a pretty massive what if that flies in the face of everything we see. The show is taking careful steps to establish Riders are unique looking, and that a certain five will be established. I don't know why everyone keeps trying to throw doubt where doubt cannot exist.

Even chumpstyle riders like Kurokage who people are already writing off as a future body, they still gave him a unique "base" suit. Lock seeds are, honestly, entirely without significance or true identity at this point. They're just tools. The belt itself controls everything.

A twin could have the same DNA so they can use the belt ..

Have they said that it is DNA specific?

Because I don't believe they did. They said it locks to the user. I don't see how a belt can make DNA contact through clothes.

EDIT: Yup, says nothing about DNA. Just the first person who puts it on.

Also, that'd be one hell of a shitty cop-out to have Gridon just have an identical twin out of nowhere just so that he can appear in the future very briefly standing in the background.

I like Micchy. We already see his desires (he wants to help Kota and likes dancing with Team Gaim) he has something for Mai and we know that he's smart along with his brother and family pressuring him to work for Yggdrasil.

Micchy might be a character similar to Mutuski from Blade, very impressionable since he's so young but has good intentions.