It's true the earlier Gonzo was best described as a twerp or a geek. He was always whiny and bratty like a little kid determined that others should see things his own way, such as him being an artist. It's most likely he started out small with acts like growing tomatoes and eating tires in an attempt to gain acceptance, no matter what he said, as he tells Kermit that he has "fans", then says "I don't play for the masses". Gonzo sort of also bought into Scooter's idea of being a female impersonator. In other words, he didn't do much thinking on what the auidience might like to see for himself, as to why his acts were such failures.
In season 2, Gonzo seemed to become more self-confident and seemed to gain a bit more respect from the auidence from acts like catching a cannonball, regardless of how much Floyd and Fozzie picked on him. From the start, Gonzo always, deep down, felt hurt and like a failure when booed offstage, indicating that he himself didn't have much confidence in himself, but during season 2 and beyond, seemingly discovering how interesting wierd things could be, Gonzo started actually enjoying his "art" with a wild zeal and persisted no matter what anyone said fullheartedly, often recruiting those willing, seeming to make him more self confident.
That's my analysis on his character development.