This post is in response to the comments Alexis left on my half-baked post from a few months ago.
1. My item #1 was not about point buy; it was about having an attackable pool of points associated with each ability score which were separate from HP. E.g. if you have 15 CON then you also start with 15 "CON HP". I don't think it would be good for anything at the moment; it was just the seed of an idea.
2) Ignore #2 and #3. Let me re-explain #4.
Think about stealth (and the detection of creatures who are using stealth) in your game. Let's call the person sneaking the "sneaker" and the one who is being snuck past the "target." The rough idea is that the sneaker picks a range to sneak to, and then dice are rolled to see how far out the target can perceive at this moment. If the dice come up equal or higher than the number of hexes to the sneaker, then the sneaker is perceived.
While I was thinking about your rules, I started to think about other scenarios in which a roll is made to see whether a creatue perceives something "sneaking up on them." For example:
Suppose that that aura of a magic item fluctuates depending on its strength. Magic can only be perceived by a creature with some sort of magic-sensing ability, eg. Detect Magic. To such creatures, a weak item is perceivable from 1d3 hexes away, a medium item 1d6, and a strong item 1d6+2.
This hypothetical rule is very similar to the sneaking rules, except that it's the natural fluctuations of the magic aura which are represented by the roll of the die, rather than the fluctuation of the target's ability to perceive the sneaker. What intrigued me about it is that I can imagine other such perception rules which are dependent on having the appropriate senses: if you have tremor-sense, then maybe a creature of 100 lbs or less can be felt 1d3 hexes away, a creature 101-500 lbs can be felt 1d3+1 hexes away, a creature 501-1000 lbs can be felt 1d3+2 hexes away, and so on.
3) Let me re-explain 5. I was actually hoping to get to something like this on the podcast.
Most (all?) rules are about measuring quantities, and mandating some relationship between them.
For example, "If you have X HP and are hit for Y damage*, your HP after taking that damage is X-Y". That's an obvious rule about the application of damage to hit points. The two quantities are X and Y. (*Assuming damage reduction, resistance, etc. has been already applied, and Y is the amount of damage actually getting through to the character.)
Here's another example: "If Cure Light Wounds is discharged on someone, that someone heals 1d4+4 points of damage (but will not heal beyond their maximum HP)." In this case we need to refer to the amount of healing provided, and a condition dependent on the max HP of the spell's target.
I believe that rules should be written so that every possible value for their quantities is accounted for. If the rule makes reference to an ability score as a quantity, then the rule ought to be defined for scores of 0, 1, and other values outside the typical 3-18 range** for player characters (**or 2-19 if you use typical racial effects). The core stealth rule ("compare dice roll to sneaker range") has a quantity created when the target rolls dice, and that number can be compared against the sneaker's range no matter what specific dice pool the target rolled.
That stealth rule is a good example of what I'm trying to get at here: no matter what number gets rolled on the dice, the rule can account for it. I think all rules should be like this. But some rules are not: for example, many of the bonuses and disadvantages conferred by ability scores are limited to the player-character range of 3-18. I don't like this. I'd prefer for rules to, as much as possible, be equally applicable to qualities that both PCs and NPCs share, because they are all entities co-existing in the same world.
Why do I prefer that? Because if the rules on how to lift doors, or add Str bonus to attack rolls, can be evenly applied no matter who is encountered, then the effect is that the players able to learn consistent mental models about how the game world is structured. Suppose the party is fighting a tough humanoid enemy. If the party's fighter can tell that the foe has no fighter levels, then the bonuses on its attack rolls must either be coming from racial advantage; from a high Str; or from some other, unknown source(s).
I recognize that the outcome in the above scenario (the party is able reason about where the enemy's bonuses are coming from, even if they don't know everything) is perfectly possible under rules where ability score bonuses are only defined on the range 3-18, and so on. I just want to make sure that MY rules for ability score bonuses -- and for everything else -- take into account the values that PCs ordinarily won't obtain, but NPCs may have.