Pretty much thats all you can do as far as a build goes for staying a kid however something I would take in consideration is special beam cannon probably will be your strongest attack so I would put 3 points into it instead of just one and not worry about maxing out Masenko or Mouth energy wave.
Okay, so I edited the tree once more to maximize the Makankosappo at the expense of Mouth Blast. But still, the Masenko's a really solid skill. At my level at the least, it's signficantly stronger than Mouth Blast.
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