Piccolo Jr. isn't quite the same person as King Piccolo though, so I wouldn't say it's fair to say he's soundly defeated him twice. Plus "soundly"? Goku BARELY won the fight with Piccolo just like he BARELY won the fight with Vegeta. Also what was the warning of an even bigger threat after Vegeta? That he'd be back to kill them all? Because that was Piccolo's message too.
Not quite, but at that point, he is more or less a reincarnation of Piccolo Daimao. He has all his memories and he is out to murder Goku. Goku barely won that fight, but there was absolutely zero question about who won either of those two fights. Goku didn't win the fight against Vegeta. He lost soundly. Vegeta had him beat even before he transformed. It was a team effort and Goku was completely broken and would've died had his friends not intervened. The warning of a bigger threat was Kaio's warning that Vegeta wasn't the root of evil. It's an allusion to Freeza. And Vegeta, unlike Piccolo, was in a position to make good on his promise. Goku was a Piccolo's superior, but not Vegeta's.
I'm talking about the obvious implication that Goku will have children
I get that, but we don't need to see it. It's not a dangling thread that needed to be explored. Goku and everyone's stories were wrapped up at the end of DB. Yes, the story could be and was expanded upon, but as of the end of DB, it was a complete story. The same can't be said of the end of the Vegeta arc.
His story arc doesn't just end here, just like your life doesn't end when you have children, lol.
Laugh at your weird joke all you want, but that doesn't mean you have a point. Goku's story arc did end. That didn't mean his life ended, just that it was completed. You can go further, but you don't have to. The ending gives the story shape and meaning. In this case, Goku had achieved his dream of becoming the champion and the best in the world. No matter where he goes, we know he and his friends are going to be okay. Everything CAN be further expanded upon, but that doesn't mean it HAS to be for the story to feel complete.
is all about Goku trying to find a suitable protector for Earth once he's gone.
No, it is not. You don't understand this series as well as you think. Goku's motivation is EVERYTHING. That's the root of everything. He helps out but he also causes many of the problems because he wants a good fight. Uub is created as a result of Goku asking for Buu to come back as a good guy because he wants to fight someone as strong as Buu without the threat of everything being destroyed. Uub taking over as protector is a bonus, but not Goku's primary goal. Goku is trying to be the best martial artist he can be, not out to save the world. Yes, he will save it because he's not malicious and he has to live in it, but he isn't above letting an enemy live for the sake of a good fight in spite of the danger it poses to others. Letting the cyborgs be created even though he has three years warning should be argument enough that the show isn't about saving the world.
You seem to imply that for some reason you can't have the show end in a way that shows the end to Goku's story as well as an end to the show as a whole.
It does show the end of the story as a whole. Goku's journey has come to an end, everything is going to be okay. We know enough about Uub and what the implications of his existence are. That's all the story requires.
What are we supposed to think when Goku leaves his family and friends after 200 episodes of being with them to take off with some random kid we just met less than 10 minutes ago?
The same thing we always knew - Goku is a warrior at heart and not the best family man. You're talking about a guy who agreed to marry Chichi because he thought she meant food. He cares about his family but it doesn't mean the same thing to him as it does to a normal person. They aren't his greatest priority, they never have been. I dont' think he's the worst family man ever, but he's never been the best. It is supposed to be a satisfactory ending because Goku is excited about the prospect of having someone strong to fight. I may not like it, but it's in character. The prospect of a fight is the most important thing to Goku and it always has been the case. It's his reason for being.
And it doesn't matter what "the audience" thinks because we aren't all one person with one opinion. Some like it, other's don't. First and foremost, the ending has to make sense story and character wise and bring closure to the story. I think Kunzait wrote a post on this very issue.
Vegeta could do it much faster
Arlia is filler.
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