Hmm... let's get unusual.
Space Harrier (Sega)
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Whilst not explicitly confirmed to have inspired the specific series, Space Harrier is an intensely important title in the history of the Rail Shooter genre, and the most notable Smash example of that would be Star Fox (which did of course release after Space Harrier, with the latter releasing in 1985 compared to Star Fox's 1993 release). My argument here is that it works, to a lesser extent, in a similar vein to how 1993's DOOM inspired pretty much the entire FPS genre since then - Space Harrier can be seen as having almost invented a large genre of its own that predates FPS.
As a result, I think it would be quite interesting to see him here - not to mention, he's an interesting pick as a retro SEGA rep, and an arcade character - giving him a surprising amount of history, as well as various different titles to represent in different ways (Fantasy Zone springs to mind, but also other classic SEGA arcade titles such as Hang-On and Outrun.)
In terms of basic gameplay, I imagine he's a lightweight, aerially-based zoner of sorts, though happens to be relatively slow on the ground and has a lot of lag on his attacks. This means that in the right hands, he can be pretty dangerous to deal with - but, he's a bit of a glass cannon in that he struggles with comboes and the like.
For visual design, I think it would be a good idea to create a Smash Original design, based primarily on his classic design with some more modern touches - an idea springing to mind being his appearance on the box art of the first SEGA 3D Classics Collection. However, it might be a good idea to include design aspects from other titles and the like, as well as a fresh coat of paint in the Smash style.
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