I doubt it's that since these are four NEW pilots which seem to signify that it isn't something that's already been seen. And the Crash Nebula pilot failed to gain an auidence so I don't think Butch would try it again. Besides, Crash Nebula may of looked different but it's comedy and tone was the exact same as Fairly Oddparents and honestly even if something looks different doesn't mean it should be given it's own show if it's still the same kind of product.
Which is what I fear from these four pilots. I'll grant that Butch Hartman isn't Seth MacFarlane who just makes shows on disfunctional families that consist of an idiotic husband, annoyed wife who may be somewhat quirky but is usually more in the right then their spouse, a weird son, an ignored or tortured daughter and some talking animal/creature/something you wouldn't expect to talk like they do who is usually the scene stealer. And at least Danny Phantom tried having a bit of depth even if it didn't really succeed IMHO. So I hope these shows are all different then each other and Butch isn't just continously cranking out the same kind of story each and every time since he knows Nick will buy it.
Man now I"m up to 7,000+ posts. Hard to believe it took me 8 something years to get that many. How long will it take me to get another thousand? Guess you're going to have to keep reading what I have to say to find out.... I hope you've been doing that anyway as I feed off the attention.