Let's say I wanted a character with a really low maximum burn, let's say 30. And a low limit (12?), because my character's a wimp with no potential for combat. But he has a lot of spirit, and can keep going where others would quit. So he has a really high recover.
Let's pause here and calculate the optimal combat for the proposed character. We want to balance the character customization options with eachother; can't have one being too much more powerful than the others.
Burn 100 Limit 20 Cool 5 Recover 1
Turn 1) BURN +29 (71/100) +29 bonus (roll 18, total 29)
Turn 2) Cool 5 recover 1 (48/100) +24 bonus (roll 12, total 25)
Turn 3) Cool 5 Recover 1 (29/100) +19 bonus (roll 16, total 25)
Turn 4) Cool 5 Recover 1 (16/100) +14 bonus (roll 1, total 15)
Turn 5) Cool 5 Recover 1 (8/100) +9 bonus (Roll 14, total 21)
Turn 6) Cool 5 Recover 1 (5/100) +4 bonus (roll 18, total 20)
At this point another max cool would allow the fighter to start regenerating this pool of burn; he's used it all up, and he's going to be unable to fight for a while. This is an all-out style of combat for the guy; 29 burn is his maximum, 30 burn on the first turn would kill him on turn 6.
So we want our wimp but high endurance fighter to be able to last at least past turn 6, at a reasonably similar power level. Let's say he wants to start off at 15; and he also has 5 cool.
Burn 30 Limit 15 Cool 5 Recover ?
Turn 1) BURN 15 (15/30) +15 bonus (roll 9 total 18)
Turn 2) Cool 5 Regenerate 6 (11/30) +10 bonus (roll 13 total 17)
Turn 3) Cool 5 Regenerate 6 (12/30) +5 bonus (roll 15 total 16)
Turn 4) Regenerate 6 (13/30) +5 Bonus (roll 17 total 17)
Now this character can occasionally burn 5 more, and keep going to fight indefinitely; he'll heal during his fight, and can long outlast opponents with lower regeneration. However, his lack of limit and burn mean that he's not going to be able to hit as hard as the other guys; The original guy virtually leveled a mountain on his first hit, while this guy's strongest hit cannot scratch the mountain; 18 just isn't going to cut it against 29.
This little test shows that Maximum Burn doesn't really have much of an effect; it should be really cheap to buy Burn. 10 points of Max Burn for 1 Credit? Limit on the other hand, is very important. That 5 point difference had a major effect on the battle. 1 point of Limit for 1 credit seems good. We did not test Cool in this test. We'll apply an arbitrary amount for now; 2 credits for one cool.
Now to set the regeneration. We'll need math for this one; setting an arbitrary amount would mean that the two characters would cost different amounts, implying the battle was not balanced.
Stat: Char 1(cost): Char 2(cost):
Burn 100(10) 30(3)
Limit 20(20) 15(15)
Cool 5(10) 5(10)
Regen 1(X) 6(Y)
Y=6X
X+10+20+10=Y+3+15+10
X+40=6X+28
12=5X
X=2.4
We're already including funky rounding when concerning rolls over the Limit stat, so let's round that to be 2 like Cool.
Char 1 now costs 42 and Char 2 costs 40. Close enough.
So you have the following:
1 Credits: 10 Burn OR 1 Limit
2 Credits: 1 Cool OR 1 Recover
Maximum 40
I wouldn't really advise going with those specific numbers; I think that Recover should actually cost more than Cool, so let's recalculate Burn cost if it's the unknown and Recover costs 3.
Burn 100(X) 30(Y)
Limit 20(20) 15(15)
Cool 5(10) 5(10)
Recov 1(3) 6(18)
Y=(3/10)X
X+20+10+3=Y+15+10+18
X+33=(3/10)X+43
(7/10)X=10
7X=100
X=14
Y=(3/10)14=4
More funky rounding FTW
So to buy 30 Burn it costs 4 credits. That's 7.5 burn per credit, or 15 for 2 credits.
It's getting too complex now, so I'll just quit. Bah.