The production of Power Rangers have been different from season to season throughout the years. Thus, fans have a different reaction to each of these types.
1. Overarching seasons
MMPR, Zeo, and Turbo were seasons that flowed from one season to the next. They never had any conclusion that the seasons were working towards. It was meant to go on forever (until Turbo forced the Production crew to end it with In Space). The only thing that these seasons had going on for them, was the changing in the status quote, and how all the characters would change as the settings and cast changed throughout the years. For some, this was lots of fun. For others, some of the changes weren't so great. To date, this style of production has yet to be tried again since the Zordon Era. Could it be due to there being less viewers? Or just the production crew still wanting to change the cast every year?
2. Translating Sentai
Lightspeed Rescue, Time Force, Wild Force, SPD, Mystic Force, OO, and Jungle Fury's method of production was to just translate Super Sentai's plots. Of course there were differences, but for the most part, it mostly just translated their Sentai counterparts. The only major element that these shows don't really imitate are the Sentai characters themselves (with a few exceptions). As evidenced when Lightspeed Rescue did not copy the family stories from GoGoFive. Some fans love this style, due to being faithful to their Sentai counterparts. Others don't like this style, as it shows how lazy the producers are being for not using their own ideas and just blatantly copying an already existing story.
My personal opinion, I used to not care much for this style, as it just copied a story I had already experienced. But recently, I thought it would be better to appreciate these seasons (not all of them. I'm looking at you OO. :P ) for doing a good job at translating their Sentai counterparts. Watching Lightspeed Rescue and Time Force in that way truly makes them something that's worth appreciating. After all, it can be quite hard to adapt Sentai. Of course, I can't really give the shows credit for story, due to them being ideas from Sentai's writers. So in my eyes, Time Force is just an "English translation to Timeranger." And did a good job at it too. Though if I'm to look for a season that stands on it's own, it would require more originality imo.
3. Completely Original
Dino Thunder and RPM. Both of these seasons have absolutely nothing in common with their Sentai counterparts. To some extent, both of these shows also parodied the franchise itself.
Unlike Dino Thunder and RPM, Ninja Storm was an all out parody style season. So it's kind of like the "American Carranger." Of course, Ninja Storm still had some serious stories. Most which were copied from Hurricaneger. Ninja Storm, being a comedy season will vary from person to person, depending on who finds what funny.
5. A mix of types
In Space and Lost Galaxy. In Space was a mix between "Type 1" and "Type 3." It picked itself up from Turbo. But it still had it's own season long contained stories. These stories were all original (except for the Psycho Rangers Arc), as well as having it's own original Space motif. Lost Galaxy was a mix of "Type 2," "Type 3," and a little bit of "Type 1." Lost Galaxy was partially connected to In Space, due to Alpha 6, the Megaship, Bulk and Phenomenus, Karone, and the Psycho Rangers. Lost Galaxy was also original for having it's own original Space Colony motif, and having a very different cast of villains. Despite this, Lost Galaxy mostly copied a lot of plots from Gingaman.