[Sunred]

MMPR S2(Thunderzord) > Power Rangers Dynasty: A season where a transfer student from Hong Kong(Red) and his new school friends battle a re-awakened evil controlled by a billionaire who calls himself Lord Zedd.
Later, they will be joined by the nosy comic relief who at first is the butt of all jokes, but becomes the White Ranger by proving himself in a mid-season episode.


MMPR S3 + Alien Rangers > Power Rangers: Ninja Stars: For this I would maintain the alien ninja concept somewhat.
Five ninjas from different rival clans escape together only to crash land on Earth after getting hit by the bad guys.
The show would be sorta like the breakfast club in the beginning, only difference being its teens from rival ninja clans who later begin to accept each other as the show goes on.
And their mentor/guardian would be a veteran surfer/hippie who says stuff like "Hang ten" or "Wipeout".


Zeo:
I would have the rangers be perfect strangers only to join forces when the machine empire raids the museum where the zeo crystals are located. Mid-season I would have their mentor be King Ranger after a near-death experience after encountering the ghost of the former King Ranger.


Turbo:
The rangers would be classmates in the same shop class. Throughout the season they gradually build their dream car. I would have Dappu in the show for comic relief. And I would like to keep it as humorous as possible so that the Japanese footage makes more sense. Last but not least, laugh track for every joke.


Space > Power Rangers Cybernauts: Have the rangers be detectives who are also childhood friends that investigate unexplainable mysteries related to technology. The bad guys would be like Museum from Kamen Rider W.