That roster looks great to me, save that I'd personally add Roll to the Battle Network crew (I don't think they all have .Exe after their names, I'm pretty sure thats just Mega Man). Shes a pretty prominent character in that series, and pretty much Mega Man's girlfriend to boot. I'd even put her in above the BN Bass actually, since he was a bit of a fringe character in that series (although I am speaking only of the first two games, I didn't play 3+, so maybe he became more prominent after 2).
And yeah, a game like that is a once in a lifetime opportunity that way. I'd look forward to pitting classic Bass versus Zero, personally - Dr Wiley's two greatest creations finally having the chance to duke it out. Although just the chance to destroy everything from the recent games with classic Proto Man would be enough to make me buy the game regardless
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Zevox