This is the second season (the first was Choujuu Sentai Liveman) in which the rangers don't directly kill off ANY of the major villains, and one of the few with none of the major villains growing giant sized.
ToQger Returns marks Fumie Arakawa's director debut and her as the first female to direct a Super Sentai work.
Breaking News Interruption: The second-to-last episode of the show was interrupted by a newscast about the death of a Japanese journalist at the hands of the terrorist group ISIS. It was long enough to push the final two episodes (and thus, the premiere of Shuriken Sentai Ninninger) back, but short enough that Kamen Rider Drive and the premiere of Go! Princess Pretty Cure aired uninterrupted.
Dawson Casting: The show establishes that the ToQgers are approximately the same age, having been in the same class and all; which makes it kind of funny that Jin Hiramaki (Tokatti) was 27 at the time, 11 years older than the youngest cast member Moritaka Ai (Kagura) who was 16 at the time.
Minor example would be Riria (Mio), who was 20-21, while the rest of the team (sans the above mentioned) are in their late teens.
The age difference between Tokatti's and Kagura's actors was given a major lampshade by Wagon in #2.
Hilarious in Hindsight:Turns out it's way more apparent as the core 5 are technically kids!
Turns out the kids are Dawson Cast too. The Returns V Cinema released in 2015 was set in 2017, and the 10 year old child actors played their real ages in that. In the series, they were one year younger but playing three years younger, as the series aired in 2014.
Rainbow Bright/Brite for Akira due to his new name loosely translating to that of the 80's cartoon character.
The series in general is usually referred to as "Power Traingers". The term is often used by fans hoping to see a Power Rangers adaptation of the show.
I Knew It!: Many fans predicted that the Rangers were still kids taking the form of adults.
Keep Circulating the Tapes: The home video and streaming releases of the show removed the ending credits because it featured clips and trivia about real Japanese trains, and the licenses for them weren't renewed. The only way to see these credits is through recordings of the original 2014 TV airings of the show.
Names The Same: Get used to calling the red and blue ToQgers Ichigo and Nigonote No. 1 and No. 2. When said Riders as well as Kamen Rider V3 meet the ToQgers in the Gaim crossover special, Mio even brings up the fact that V3 isn't called "Sango" note No. 3 like she is. As it turns out, Sango would come later.
As it's pronounced 'zed,' comparisons to a slightly more well-known (in America, anyway) lord named Zedd have been mentioned.
Especially since Gritta is going to be his bride. Rita and Zedd, Gritta and Zed!
No Export for You: Became the second Sentai (After Go-Busters) in the Saban Brands era of Power Rangers to be skipped in favor of adapting Shuriken Sentai Ninninger; in this case, it's generally assumed that it would be nigh-impossible to adapt the show for American audiences due to the use of Japanese trains, as well as railfanning being viewed as a niche hobby in the United States. Although this might be subverted eventually, since Go-Busters later got adapted as Power Rangers Beast Morphers.
Orphaned Reference: The opening narration mentions that Ressha Sentai ToQger will depart at 7:30, a reference to the show's timeslot at 7:30am on a Sunday. This reference is lost to anyone watching via home video or streaming, especially since Super Sentai has aired at 9am since 2017.
What Could Have Been: Hacking the DX ToQ Changer revealed several ToQ Ressha which remain unrealized. They include Rider Ressha, Gaim Ressha, Dump Ressha, Dozer Ressha, Mixer Ressha, Crane Ressha, Jet Ressha, Blizzard Ressha and Ring Ressha.
Then there's the Legend Ressha. While the Kyoryuger Ressha appeared on-screen as a Humongous Mecha in Kamen Rider Taisen, then as a mere trinket in ToQger vs. Kyoryuger, the Changer has sounds for all of the first 37 Sentai. The Go-Onger to Go-Busters Ressha are toy-exclusive, derived from the Red Ranger's mecha like the Kyoryuger Ressha, while Goranger to Gekiranger have no form beyond SG Resshanote Generic train cars with the eponymous Sentai plastered over the sides.
, and as an individual series on the ToQger Wiki