Overall pretty good. I personally don't like clip art, but that's irrelevant. Styles are gonna vary, and I think you've found yours. Or you were just lazy, either way, you get it.

The voice, intro, and sound are a bit lower than the outro credits, so perhaps leveling that out would be nice.

A bit slow paced, but I think someone has mentioned that already.

I would argue that not using a tool such as tweening in your arsenal is a sin among animation. Tweening can be really useful and add cool visuals when utilized properly. I say do what you want, but make it look good!

I'm gonna follow the series, hope to see more. :D

Not bad. If your looking for any tips, the only one I would give is to look up Animation Phenomes. This will help give a more accurate lip sync (if you think you want that in your animation, I understand certain styles may not use this technique on purpose). Hope any of this helps! Keep em' comin!