Plenty of good ideas so far

I would definately watch a new version of Astro (although all of us would)
I too don't think Skunk would make much of a main villian, he's more a single episode or small arc villian who seems to only cause trouble when he steals something that gives him an advantage and helps him to steall more things.
Tenma on the other hand makes a good villain for the long run, I enjoyed his entire character arc, and the 2003 version made nice additions to that. Shadow could have effectively replaced Tenma as the villian while Tenma eventually makes the same mistakes with Astro and eventually is captured. If 2003 had continued I could see Tenma possibly becoming an ally to Astro, and knowing the most about Astro he could open new plots and thus arcs.
So heres an idea to think about, instead of starting at the start again, what about continuing either the 03 or 80's series.
(of course we know such a thing would never happen because in order to create a sizeable fanbase for the series a production company would need to start again to draw new people in)
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