This movie seems to be very strange and puts it's own twist onto Yu Yu Hakusho.
I recognized Yoshi as the role of Yusuke Urameshi, Winnie the pooh as kuwabara, ect
The crude drawings added an extra bit of comedy to the entire movie itself.
I would have liked to see more animations during the intro.
The movie stops on a frame where the characters are standing together.
The music keeps playing.
A quick fix would have been to add a text saying, "Too lazy to keep animating. Now listen to music"
You could have also added more animations into the intro itself because your concept has a lot of potential for comedy.
The sped up version of the theme song sounded very funny.
The music added strangeness to an already weird movie.
I wouldn't bother adding any kind of explanation for anything within the movie.
You might get a few bad reviews bitching about how it doesn't make sense.
I would recommend intentionally making Yoshi Yoshi Hakusho even more weird and confusing.
Confusion can sometimes induce laughter because of the extra element of surprise.
Make some episodes of Yoshi Yoshi Hakusho.
I look forward to it.