== This is garbage ==
Overall Score: 4
OK, it appears this "successful and Long-Running Animated Cartoon Series", after 14 years, you only managed to get 320 subscribers on YouTube and 80 here, and I think I figured out why.
It is a crap series. No seriously! In this episode Sergio (or specifically an evil version of him) is literally surrounded with a pile of garbage for 3 minutes and builds a portal. This could've been cut down to just 30 seconds, or at the very least each scene could be half the length and it wouldn't be compromised in any way
That 'Wastiest LAND!' sign appears for 7 seconds? Try 2-3 seconds
0:53, the garbage structure is built and falls apart is 18 seconds. Can be conveyed in only 5 seconds.
1:11. Evil Sergio takes 4 seconds scratching his head before biting into the biscuit and chews for more than 4 seconds.
As for the visuals, also shit. The garbage pieces use very crude outlines and overuse an ugly gradient, Sergio's skin outlines are thinner than his clothes, and it's still a motion tween, just like you did in 2008, and utilising basic shapes. It doesn't feel like it's been hand-drawn, it feels very artificial and it just doesn't look good. Even LegendaryFrog, for as infamous as he was, was able to make better tweening animations in 2002.
His elbows also bend backwards in 0:43.
TIPS:
Try learning some actual drawing and animation techniques. It shouldn't be hard to find courses or resources on this subject. It's OK to take a little break in order to learn something new.
Oh and also try to fix up your pacing and not pad out episodes for time.
The series itself also feels very choppy. Try using a higher framerate. 24 frames per second is a good benchmark, although 30 is better suited for most video displays. As for the rigging, try some faster movements and ease in and out when needed (that is slow down during the start or end of a movement. For Flash, they're called motion tweens, but it might be called something different if you're using a different software)
~frog~
Graphics: 4 | Sound: 6 | Pacing: 2 | Style: 3 | Entertainment: 5