The key is the execution here. Sure, he was shoehorned in, but was really subtle and far from the stereotypical kid hero. His role was smaller compared to others, but it was still a substantial part of convincing Ashe to not get revenge on the empire, thereby preventing her from becoming a villain. They may have been forced to include him, but I think they went about it in a very smart way, which is why aim personally really miffed by people complaining about Vaan's inclusion. But that's just my opinion
I'd personally love it if the Saga series got a revival so I could finally play all of it! I wanna check out that game that made The US branch of SE apologize to its fans.