Executive Meddling: Eric was originally slated to die, just like his counterpart in Timeranger. The writers were skeptical that Fox Kids would allow this, so they filmed two versions of the scene: one where he died, and one where he lived. Fox Kids, as expected, vetoed the death. It worked out for the better, considering his performances in his two teamup appearances.
Also, the originally planned ending had Jen staying in 2001 with Wes to keep the recurring theme going. But due to this trope this was thrown out the window, resulting in executive producer Judd Lynn quitting the show.
The team-up in the next season did have Jen return to the present, though it's never stated one way or the other whether she stayed this time.
Mean Character, Nice Actor: Well, at least, that's what Eric started off as. Either way, actor Daniel Southworth is actually nice in real-life and is very funny; he's definitely less serious when compared to Eric. If you've seen him speak at panels at conventions — like the one for the Time Force and Wild Force cast & crew in Power Morphicon 2014, for example — he's usually the one who gets the most laughs out of the audience.
Missing Episode: According to Shout! Factory, one of the original uncut episodes was destroyed, though, currently, it is unknown which exactly it is.
Old Shame: Averted heavily. All the starring actors look back very fondly on their time as Ranger actors, and are still friends to this day. Erin Cahill still attends Ranger panels and events and has spoken highly of the quality of the series, and Jason Faunt notably returned to the role of Wes for Power Rangers Megaforce.
Promoted Stuntman: Years before Dan Southworth got the part of Eric — during the Zordon-era, to be exact — he was a stunt-double for Austin St. John (Jason) and for Johnny Yong Bosch (Adam), when both their characters were suited up (though of course it's well known that those two did most of their own stunts when unmorphed and on a few occasions when they were suited up).
Separated-at-Birth Casting: Daniel Southworth as Eric Myers looks so much like his Japanese counterpart, Shinji Kasahara as Naoto Takizawa, that at several points the series uses faraway shots of Naoto directly from Timeranger.
Talking to Himself: Alex and Wes, both played by Jason Faunt. Justified as Alex and Wes are related, though how exactly is never elaborated on. It's been said that Alex is a descendant of Wes, though not necessarily a direct one.
The writers originally planned out a series where the Rangers traveled through time and fought across different time periods. Then they discovered that Mirai Sentai Timeranger didn't actually feature the characters actively travelling through time: they travel once to the year 2000AD and stay therenote and briefly the Mesozoic Era and early 18th century. The writers would later indulge their desires for historical crime-fighting in the two-part Trapped In Movie Land episode "Movie Madness", scenes from which would later be spliced into the opening sequence to imply that... yes, the Rangers actively travelled through time and fought across different time periods!
Alex was originally supposed to become the Quantum Ranger, but this was changed to Eric, who was a more straightforward adaptation of his Sentai counterpart.
Daniel Southworth was offered the role of Wes/Red Time Force Ranger; but, as fans already know, Jason Faunt got that role instead. Interesting to note: in the show, the team was hoping that the Quantum Morpher would go to Wes.
Just before that, he auditioned for the role of Lucas. But, apparently, the crew thought he was "a little too intense" to be the Blue Ranger.
And in the past, Dan had also auditioned for the role of Adam from season 2 of MMPR, but that part went to Johnny Yong Bosch instead (while Dan continued to do more stunt work, including being a stunt-double for the latter as mentioned above).
There was talk of a movie, but a possible SAG strike (which ultimately didn't happen) as it would have entered pre-production resulted in the studio opting to play it safe and cancelled it (it's likely that the sale of Fox Kids/Fox Family to Disney at the time also played a role). This also cut an extra episode order, leading to a discrepancy in the capture of mutants (Ransik had one left in his prison in the episode 'Circuit Unsure,' yet the next episode opens with the prison empty and the Rangers declaring every mutant except Ransik recaptured).
Allegedly, the show's Darker and Edgier nature nearly led to it airing on Fox primetime alongside The X-Files! (The only other time that happened were a few sporadic Primetime Power Rangers airing during MMPR season 2, alongside episodes of X-Men.) It ended up on Fox Kids in the end, though, apparently to "maintain brand consistency".