This is a great idea that I have never even considered before! While I didn't watch Clone Wars and don't watch Rebels, I've heard good things about both. It probably would have to be a Netflix series or something like that, but it could work out really well if the right people were involved.
I started watching Clone Wars with my son, thinking it would be an amusing kids show that would be less painful to endure than, say, Ninjago or or Spongebob Squarepants. I wound up liking it even better than the prequel films. Better characterization, more interesting plot lines, amusing dialog. Heavy with the usual "idiot ball" cliches, but still enjoyable overall.
I had similarly high hopes for Rebels, and it hasn't disappointed, especially with the recent cameo of Darth Vader, who casually orders a minor war crime in one scene and then just as casually whups everyone's ass in the next.
If it's done right, if it keeps to the style and tone of the Abrams movies and blends in enough of the old TOS charm without becoming hokey or fanwanky, it can be a thing of beauty.
Animation, unfortunately is a bad medium for ANY action/drama type program for the foreseeable future. Animation networks want psuedo-action comedies aimed for the 8-tween market.
Which is why an animated series based on TNG or Voyager would be an exercise in futility.
"Pseudo-action young-adult entertainment" is pretty much Abramsverse in a nutshell, so much so that almost ALL of the Trek novels based in the Abramsverse have been young adult titles.
And that, in hindsight, shouldn't be that surprising. TOS survived as well as it did in syndication because its original fans discovered it as children and teenagers and then stayed loyal to it as adults. If anything, Star Trek should return to its roots: speculative science fiction sophisticated enough for grownups but fun enough for kids.
I'd be willing to keep an open mind, but I would be less enthusiastic. I watched Star Trek shows constantly as a kid, not cartoons, heh. Point being, my perspective is a bit skewed, I guess. I've never had a soft spot for animation. Also, I'm really big on actors, and acting, and VA work only goes so far to scratch that itch.
As I said, though, I'd try to remain open. I'm sure I'd be happy Trek is back on TV, at least.
Hell, I grew up FOX Kids' Saturday morning lineup. X-Men, Spider Man, Iron Man, The Tick, Animaniacs when I was bored. Sometimes jumped channels over to CN when they had Robotech or Transformers. Even watched a couple episodes of TAS.
And people like me who grew up in the Anime Era remember treating movies like Akira and Ninja scroll like serious films and not as "kids show" productions that nobody else cared about. I remember once my dad asked me why they didn't bother making a live-action version of Ghost in the Shell and asking him "What the hell for?"
Animation has ALOT more potential than most people believe, especially if you have the right creative team and the right marketing. Star Trek has been missing out on this potential for a very, VERY long time.