In 1Player score is used only for highscore, and some of the ways to gain points is very skewered or unfair, or just downright broken. For references to how score and points works in the game see: Here and Here.
And to detail each on in more detail:
The current rules for Consecutive hits and Combo hits rewards you for attacking with many light attacks in high combo numbers. But doesn't reward you for making a short combo that does a lot of damage. It is skewered toward a certain play-style which can be summed up as Crystal+Electra.
By having a way to reward people for doing damaging combos, it would even out the score disperancies. An example would be to have a “Combo Damage” bonus, that gives you some bonus points depending on how high damage you did in average over a combo.
You are already rewarded for not getting hit by receiving the full health bonus, adding double that on top is just needless. And penalizes a player that gets unlucky or messes up a single key press by losing 400 + damage in points.
Just keep this to Health only, and no Perfect Score. (You can still have the “Perfect Match” pop up, but no points reward.)
You get free bonus points just for learning to spam a special move or two at the end. Completely useless. You already have a reason to use this in Tournament Mode, to get the upgrades and unranked characters, no need to get free points as well.
Just remove points gained from these.
This is 1Player only, which is the only place where Highscore matters. And these two hidden characters are worth a crazy amount of points each. Thus the most important strategy for getting a Highscore in 1Player is to beat these two perfectly, and the rest of 1Player becomes trivial compared.
As it stands you might as well make a own game mode with just Fire & Ice for highscore, because they're the only things that matters. All of the actual 1Player mode is just there to differentiate between someone that had identical highscore from Fire & Ice.
Remove Fire & Ice from 1Player mode completely, or remove all points from playing against them. Personally would put them into Tournament Mode instead.
You earn more points by win:2 lose:1, than win:2 lose:0. 2 wins will give you same amount of points. But you also gain any combat points from the round you lose. So optimal is: round:1: beat enemy to 1% then lose. Win Round 2+3 perfectly.
Winning 2-0 should be better than winning 2-1 by score.
Easiest fix would be to completely negate any points you gained in a round you lost. Other options would be to have a win reward or loss penalty to even things out.
BUG: This causes even more problems with Fire & Ice, as this can be abused to fight Fire 9 times in a row, perfect 1 and lose 2 by 1% life on fire, to tack up insane amounts of points. Then finish Ice on the last round before going to Kreissack.
The new Scoring system would look like this: