I love Patalliro — both the series and the character. I'm well aware that most people are in for the pretty boys and so am I, but I can't deny that Patalliro as a character is very interesting. He's mostly there for comic relief, yes, but he does have some fantastic character development in the anime. Although not many, there are some great moments that dive into his character (one example that comes to mind is the Robbie incident). Naturally, I love seeing his character getting explored.
The canon establishes that he is mature for his age (referring back to the sparse moments of clarity he had in the anime) and yet I get the impression that he wants to hang on to his innocence. He wants to be king because it is his duty. If he doesn't do it then nobody else will, and perhaps he's not entirely hating this position, but he is not exactly prepared for it. Think about it, the king's death is quite sudden, although already anticipated, and right after it Patalliro is expected to take the throne. He's a ten year old boy that had just lost his father. Instead of being allowed time to grieve for his parent, he gets this enormous responsibility on his shoulders.
Patalliro's behaviour is always unpredictable, silly, and borderline dangerous. I'd call it childish and attention seeking, but sometimes it feels like an act. Sometimes his actions get so outrageous that I'm sure they might come as a surprise to Patalliro himself. I see this as an act of saying I'm still a child and I want to be a child. I don't want to be stripped of this — I want to keep doing silly things and make jokes and be myself and fuck it, I will.
We know that Patalliro is not dumb by any means. Etrange pretty much confirms that by revealing details of his infanthood and later, he builds robots from scratch, at 11 or so. He's undeniably gifted and everyone is well aware of hat. But he's also very lonely.
He does have the ability to do his work, not get into danger and be a responsible king. He can meet the expectations imposed on him, but he does not want to. He's entitled to his childhood and he does everything he can to live it the way he thinks he should, even though that might inconvenience the people around him. Ultimately, Patalliro choses his emotional well being over his duty and responsibilities, fully aware of that entails.
I can't judge the morality behind his decisions. He does get in trouble a lot, and he does get other people in trouble more so. He causes pain and emotional distress to people, and learns his lessons from it, the way any kid would. What I can do, instead, is admire the complexity of his character and the masterful writing of Maya Mineo.
Anyway, watch Patalliro you fools!