Megas

Operation Overdrive's highest point was the Red Ranger, he's honestly one of the stronger Red Rangers

Ninja Storm was pretty good, though I think it's on the bottom half of the spectrum. Though I still have yet to see Jungle Fury. I tend to be on the minority in regards to Ninja Steel, in that I think it's merely the most okayest Power Rangers show

@TheAnimationFanatic I think Turbo was that harsh lesson that they can't keep using the same cast as the show went on and they had to hire a new crew for each season if they wanted to keep adapting Sentai

Disney Era had SPD and Dino Thunder, so it's automatically cool in my book. Operation Overdrive and Mystic Force are the only ones I didn't like, but the rest of the seasons were good enough too make the Disney era worth it, and at least it got to end on a high note with RPM

Samurai is a verbatim reskin of Shinkenger. The problem is that it tries to americanize a sentai steeped in Japanese culture and mythology.