I was saving them up for formal publication (for free), but that is probably never going to happen, since I am far too chaotic. So this is a somewhat motley collection of various rules.
And I say "rules" rather loosely. Most of my game has grown out of a set of three defined axioms and rulings are always ex tempore. In effect these are worked examples extracted from my head with the aid of a trepanning chisel.
So I should probably start by explaining these axioms.
The First Axiom
Everything has a level (which is quantifiable and not an abstraction). This level is relatable across the game system, so level of place, nobility, title and character are all comparable.
[In effect this isn't quite true because magic (both items and spells) has a level that is half the value of a character level. However doing so eases conversations with mainstream D&D players.]
The Second Axiom
The basic classes of Fighter and War Mage occupy opposite poles of a spectrum of ability. Fighters are the experts in melee, whilst War Mage are the experts at spellcasting. This is reflected by giving the Fighter a base d10 for their hit points and melee damage, and a base d4 for their magic points and magic damage, whilst the exact reverse is true for a War Mage.
[Although when you start adding other classes into the mix it gets much more complicated. For example, Demon Hunters (Clerics) are the second best at both fighting and spellcasting, and Bravos (a subclass of Fighter) gain increased hit points and increased spell points.]
The Third Axiom
The six characteristics are well defined. For example Strength is used when you attempt to do something physically through the application of force, whilst Dexterity is used when you attempt to do something physically through the application of finesse. The spiritual characteristics (Intelligence, Willpower, and Charisma) mirror the effects of the physical characteristics in the spiritual world.
Because the characteristics are well defined they define the nature of the character. The corollary of this is that many of the game systems should refer back to these characteristics when they apply to a character, and that the player gets to choose how they affect the world.
[The classic example of this is a saving throw against a Wand of Paralysis. The player could choose to take cover from the wand wielder (and make a save vs Wands and Staves [Int]), to avoid the paralysis ray by dodging out the way (and make a save vs Breathe and Blast [Dex]), to resist the magic of the wand (and make a save vs Magic and Spells [Wpr]), or to resist the effects of the magic (and make a save vs Paralysis and Petrification [Str]).]
The Fourth Rule
This is probably a rule I should mention here (because I probably won't mention it anywhere else), which, while not really axiomatic, is still fundamental to the design principles. A bonus that originates from natural abilities generally increases the size of the die that is rolled by two sides. So a War Mage (base melee damage die of d4) with a Strength of 14 (+1 Strength bonus), now has a melee damage die of d6 because of their strength (and so may wield a short sword in one hand).
On the other hand a magical bonus is added to the roll. So that self same War Mage wielding a +1 magic shortsword would roll 1d6+1 for damage.
[The obvious place this breaks down is the d20 roll for combat. Ideally a +1 strength bonus should mean that the character rolls a d22 to-hit. But unfortunately these larger dice are still relatively unavailable and for ease of play I want a single die that is rolled. So a d20 with added bonus it remains.]