Took the time to trudge through the awful quality Hands of Time episodes on youtube today when I found this gem; the finale in HD and decent audio.
This episode specifically is probably my favorite of the season.
Though to address the season as a whole, Hands of Time turned out to be my second to least favorite season. It's not horrible- certainly a step above the preceding special, but falls short on properly conveying the characters as they've come to arc throughout the series. They just kind of seemed like watered down versions of effectively who they were at the beginning of the show(I'm talking pilot/early season one). This can be most clearly attributed to the lacking presence of the Hageman brothers in writing... It's like the writers were just given the story bible as their guide for how their personalities should be and didn't/couldn't account for the fact that these characters have gone on some pretty insane adventures beforehand- and the inherent character growth that follows. That, and just certain small inaccuracies or odd moments have me coming off this season sort of bitter.
The new characters introduced this time are rather solid though. I dare say that's partially because I don't have any expectations as to how they're supposed to act, but beyond that, they're actually fairly amusing in their own rights(especially Acronix and Crux). They kept the show interesting while the protagonists were frustratingly inept. They, and just a lot of fun(albeit fundamentally flawed) concepts keep the season just a notch above Possession for me.
Also, the ending puts our ninja in a very interesting place, so I'm still rather excited to see what the future brings for Ninjago's TV canon.
And no, you don't need to worry about anything being retconned for the movie canon.