Not even bad...
Pretty frickin' awesome, there. At least in comparison to... y'know... other flash-based animations. Plus, you managed to at least keep the power levels SOMEWHAT intact. I mean, sure, Vejitto's insanely strong and a Majin form would be just ridiculous, but you didn't try to water it down like most fanboys (or as in DBGT), instead opting to include an SSJ2 Mystic form. Since you don't have much time to have stuff occur in any one episode - and thus can't afford to have the more scrutinizing viewers thinking about plot inconsistencies, or else they'll be half-out for the whole episode and blam it - it was a good decision to at least throw in some question as to how strong anyone is.
Though, I feel I should tell you this: In SSJ3 form, at that point in the story, the fusion between Goten and Trunks could only be maintained for 5 minutes, as opposed to 30. And the Goku half of Vejitto would probably know that. So, I dunno, maybe in the next thing, just kinda... whatever. Just bringing it to attention.
All in all, a very damn nice animation. Woot for you.