I personally think Rebels has a lot more potential than TCW because that show is pretty much all over the place. TCW has the benefit of somewhat self-contained arcs to make “movies” out of, but the episodes that make up those arcs still feel episodic when mashed together (often jumping from one character to another). Rebels has a much more consistent progression for the characters and the story, so you could easily just trim down the fat and have a fine streamlined version of the series.

As to whether it’s movies or episodes, maybe the best way to structure it would just be to not worry about the structure. Like, season 1 is a two hour movie, while season 2 is two movies, and season three is a few hour-long episodes, etc. Whatever works.