I think a good match up is any of the Fox characters against Ness or Lucas. Seeing as how they can absorb/reflect eachothers energy attacks, it would be a good match set up. Of course, the Fox squad having more advantage, since they dont base all their attacks off energy like Ness and Lucas. Fox squad would more than likely win, if played well, being able to reflect nearly all Ness & Lucas' attacks can be a hinderence.
@ Mega Luigi: Im not sure Ness is very good against Samus, seeing as he can only absorb one of her attacks. He still holds a small advantage, but Samus' power lies in her
great range of attacks. She would still leave a heavy dent.
Same with Lucario, except he plays more close game,
where predicting his energy attacks (or lack thereof) would be straining. Lucario could put up more than a good fight against Ness, but like I said with Samus, Ness' energy absorbtion doesnt provide a good enough difference for any advantage to be spoken of.
Now, I know some people wont like this, but it must be said. Mario is a good match against any character. His cape slap has got to be one of the best moves in the game. Being able to reflect any attack as well as turning someone around without stun is a hell of an ability. Couple this with his all around decent play, and his unbeleivably easy to learn controls, I think Mario shoud be Top Tier. This is, however, only my opinion.
There are plenty of disadvantages to Mario as well since he favors no specific play style. In this sense,
Mario is good against noone, but he is not bad against anyone either. This is probably why he is middle tier (i think) and not higher. Still, his cape reflector should be taken higher into account. That, and
the fact that he has one of the best edgeguards. (meant to add FLUDD)
Mario is an all-around good character, but he is also an all-around bad character, depending on if your looking at the glass half empty or half full.
Hope this help Kingslayer. Nice thread btw.