[Matrixbeast]

I only really have to touch upon three of your points.
First, concerning the behind the scenes problems with some cast like ASJ and JDF, it's just simply because it doesn't matter. He's talking about Power Rangers, not the beef between two actors. While he does bring up some behind the scenes drama, it's only because it may be relevant (Danny Slavin's hesitance to return for Lightspeed's crossover and Forever Red, for example). Bringing up a mild feud between two former co-stars would basically be the equivalent of fanning the flames.

For In Space, I felt it was a nice send off. The powers were always shifting and changing. TJ and the Turbo rangers, who proved their mettle during Earth's time of need, going so far as to explore the cosmos, were more than deserving to stand as the champions in that scene than someone like Jason, who ditched the team to head to Australia without a moments notice. While the original rangers not returning was a little disappointing, the "It's them?" reaction held a lot of weight to me. These weren't the rangers goofing off in high school then saving the day in an afternoon. These were the rangers who, when villainy reared it's head, they actively sought to stop it.

And, as for Mystic Force, the issue stems from the fact that Nick's destiny basically marginalized the team. It went from 5 people working to overcome a foe to 4 people holding up one man to fix the world's problems as their mentor showers that one man with praise.