PARAMETERS

I'll give an example of a game whose parameters and formulas made a good impression on me, which is unlikely to make it into this discussion otherwise.

Kamidori Alchemy Meister is a visual novel/strategy RPG hybrid, much heavier on gameplay than most hybrid visual novels. The game contains explicit sexual content (I actually personally believe that explicit sexual content can have a legitimate place in works of artistic merit, but the sexual content in Kamidori Alchemy Meister tends heavily towards the gratuitous.) On the gameplay side though, it's exceptionally well devised, and uses an unusually simple system which actually turns out to be remarkably well balanced and suited to the sorts of challenges the game presents.

Physical attacks are determined by the formula of ATK-DEF, where the defender's defense power is simply subtracted directly from the attacker's attack power. An attacker with 50 attack power hitting an enemy with 25 defense will do 25 damage, an attacker with 100 attack power hitting an enemy with 25 defense will do 75 damage. There is no randomization, and the results are totally predictable in advance of each move. Most other combat formulas are similarly simple. There are various multipliers or dividers involved when dealing with elemental weaknesses or affinities and such, but again, these are all simple and deterministic, and their results can be predicted in advance.

On the other hand, once you progress beyond the early stages where you're still picking up the game principles, there tend to be enough moving parts on a battlefield that it's difficult to extend precise predictions more than a few moves in ahead. Maps are often extensive, and unexplored portions are hidden from view, including enemies within that space, so new threats are often produced unpredictably over the course of a battle. Even though you can usually determine the precise immediate consequences of a move, gameplay still tends to revolve around calculated risk. Moves whose immediate consequences aren't entirely predictable don't come into play until much later in the game, and add another element to the risk management, where you have to weigh their potential usefulness against moves whose results you can be certain of.

Number values stay fairly low over the course of the game; you're never going to hit 999 damage with an attack, let alone 9999. But the game still manages to implement a huge scope of mechanical character growth from beginning to end. Like the Disgaea series, the Kamidori contains extensive super-endgame material, where beating it once opens up a lot of new content which is more challenging than anything faced in the initial playthrough. The game contains three distinct main plotlines (in addition to a huge number of sidequests,) so accessing the New Game+ material (which constitutes a really surprising proportion of the game,) doesn't entail playing through the same main plot repeatedly.

I also found the game's take on weapon attack power interesting. While, like most games, the character's attack power is their strength plus their weapon's attack power, that attack power is measured against the baseline of their most basic weapon. The attack power for bottom tier weapons is zero, and early in the game, weapons differentiated by a single point of attack power will result in meaningfully different performance in battle.