TGM suggested a system like
Touhou's.
A character is rated simply as having a favorable (+2), unfavorable(+0), or even(+1) match-up to each other.
The score is tallied and measured against that character total number. It's simple and you don't have to worry about assigning arbitrary numbers to any particular match-up.
If I were to assign Pyroak and Vitalimar numbers for example:
Oak:
Ohm Fid Ant VD Rev Gem Kril Soil Kit Arg Vit Skul Casc Total
1 __ 1 __ 2 _1__ 2 __ 2 __0__1_ 1 _ 2 _ 2 __ 1 __2__ 18(+4)
Vit:
Oak Ohm Fid Ant VD Rev Kril Soil Kit Arg Skul Casc Total
1 __ 0 __ 1 _ 0 _ 1 _ 0 _ 0 _ 2 _ 1 _ 1 _ 1 _ 0 ___ 8(-6)
All these assignments are, of course, based on what I've seen, but it's an interesting system and I'd like to see how others might compose their charts.