These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Crazy Awesome: Buck's exploits. Also Sid being able to adequately handle a gun!
Ensemble Darkhorse: Sam and Terry, in spades. In fact, Sam and Terry are such EnsembleDarkhorses that a spin-off Fanfic is being written that explores their love story and is meant to be a POV Prequel/Sequel of sorts to the original story Lost In Time: Origins.
How could Hudson have been forgotten? Heck, his status as an Ensemble DarkWolf is part of the reason why he is so popular with readers!
Fanon: The Series has a spin-offFanfic written by another author called Lost in Time: Destiny, that Word Of God accepts as canon.
Fridge Brilliance: Due to a combination of inattentional blindness and the fact that everyone accepts surnames in general, this has caused many of the readers to gloss over the obvious clue in James Hudson's names - the fact that he has a surname, because everyone has readily assumed surnames as so natural that even when a dire wolf has one, it is given no real importance (by the readers) because it just feels natural to them to accept it as such with no questioning of the fact.
Fridge Horror: A good example is the implication that all time has been destroyed because of the human expedition never making it home, and so humanity had no idea what effect it would have on the timeline...well, till they wipe out most of history in the process...
Mary Sue: An aversion, Word Of God has admitted that the characters essentially took control of themselves, notably main character Frank and also Terry, who was originally set to be a Complete Monster.
Nightmare Fuel: Frank's terrifying dream in chapter fifteen of Origins "Latent Image" as he finds himself in the midst of the Troubles again, faced with his worst acts spread out before him in the appearance of an injured and dying little girl.
Portmanteau Couple Name: "Serry" for Sam/Terry, the Ensemble Darkhorse couple of Origins.Word Of God approves. :) There's also "Mellie" for canon couple Manny and Ellie, but that's more fandom than this series, but still deserves a mention since both are couple names.