Well, that series and Battle Fever J (which was originally supposed to be a Captain America series) were both co-produced by Marvel, so it makes sense.

This ratchets up my interest in Ninninger tenfold.

I love the series, but it's not without its faults. There's a lot of filler, the villains are all under-developed except for one, and the plot isn't very strong. There were a couple of plot threads that could have led to something interesting but ultimately went nowhere. However, the suits and action are both excellent, the character development is interesting, and some of the episodes are just straight up fun. The RPG episode is one of my favorite Sentai episodes.

It's not a perfect Sentai, so you probably won't be floored by it, but the positives outweighed the negatives for me.

Or how Battle Fever J was co-produced by Marvel? Battle Japan & Co were, during the show's early development, called Captain Japan (etc) and were supposed to be official, international analogues of Captain America.

I agree, though, that a lot (most?) of sentai's bad guys are already riffs on familiar American super villain archetypes.

One way I could see this idea being fun is if each of a season's villain generals were oblique references to a specific super hero's rogues gallery. Sort of like how the Kyoryuger's generals are references to Wizard of Oz. It might be fun to see a bad guy team made up of a killer clown, a woman dressed like a cat, a man with one side of his face burnt off, a green guy based on question marks, etc... (though designed distinctly enough to avoid copyright infringement :lol).

Should the Sixth Ranger of Zyuohger being Alien or Human?

Zyuohger got 4 Zyumans and 1 human

I think it should be human. The bad guy turned good has been done pretty recently (ToQ)

I wonder if the HUMAN Sixth Ranger will be funny one like Shinken Gold or if they want Zyuohger to be a Timeranger-type group since Zyuohger is 40th anniversary of Super Sentai, he could be a loner-type like Time Fire

Having a Sixth Ranger as a human make sense because Yamato need someone to trust with in term of keeping Zyuman's secret from his uncle and every human beings

High Evolutionary and Mister Sinister.

I know it sounds crazy but can Super Sentai have a High Tops (Trainers)-Based Changer?

I agree :)