More expensive or complex? They don't seem to like doing Jedi in robes too often, though this arc they seemed to do that a bit more as well.
I agree, it's not a good fit for Sat Mornings... Friday night suited it much more as it's clearly aimed at more than just kids, but yet wants that audience as well. I felt they really dumbed this arc down... Forgetting the insurgent parallels, which I don't think they care if a kid gets it or not, they dumbed down the combat tremendously I felt, and just made it seem "spiffy" for eyecandy for younger viewers.
I liked the concept of orchestrating a war via the Rebels and stuff, I just felt they royally **** the bed on presentation. Like I noted above, Ryloth, Geonosis, Cristophsis... They've done combat scenarios far better in every season at some point. Umbara, the initial episode with Fives & Co., Kamino, and for the most part all of their space combat sequences with a few quite notable.
This seemed like they were trying too hard to make it aim at the younger audience and more away from the adult. Really disappointed me overall. Stuff like this makes me dread the thought of them trying to do more toons at some point, for other eras Lucas may be considering covering.