Diablo 3 and Character Shape
In Diablo 3, the player can equip skills from categories. They start with only a few skills available, but leveling up gives them more actions that they are able to slot into their Limited Action Set, as well as more modifications to those Actions that do things like change the element of an attack or change its secondary characteristics.
Additionally, In Diablo 3, the player can equip items which modify the conditional value of their abilities. Sets add a great deal of conditional value to specific abilities that the designers want to create a gameplay pattern out of, and Legendaries add sharp conditional value to specific abilities or to systemic hooks like "Using an ability of Category X", Resource Cost/Availability, etc.
However, despite the malleability of a Diablo 3 character allowing quite a bit of novelty within one character class, the "shape" of a Diablo 3 character is always essentially the same. The closest this comes to not being true is the Hellfire Amulet, which uses the Legendary Affix system to add a 5th Passive to your character from the list of Class Passives. This is exciting because it enables builds that otherwise don't work and rewards the player that understands all the Passives they have available by letting them figure out how to get value out of this item.
By "Shape", I mean "how the possibility space of player strategic choice intersects with the verbs and adverbs used by the player during gameplay". Let us illustrate with bad mspaint.
Here is a Standard Diablo 3 character at maximum level. They have 6 selectable active abilities - the player's Verbs. These will be activated by pressing 1/2/3/4 and Mouse1/Mouse2, by default. Each of these 6 abilities has a Rune that modifies how it works, slightly - an Adverb. The first-order scope of any given rune is limited only to the ability it is modifying. For example, a rune for Hungering Arrow says "Increases the chance to Pierce an enemy to 50%", up from the skill's baseline chance of 35%.
On top of this structure, they then have 4 Passives, which are still Adverbs - they modify the outcomes of abilities or the context in which those abilities are used - but they are not constrained to modifying specific Verbs. In the case of the Alacrity passive in the Hellfire Amulet screenshot above, it increases the attack speed of any Generator-category ability by 15%.
Now, outside the Hellfire Amulet example above, there's no real way to modify the "Shape" of a Diablo 3 character. There do exist some builds that might equip an ability but never manually cast it, but even in those builds, you're equipping 6 abilities, 6 mods, and 4-5 passives. Some gear does as well provide additional mods - for example, the 4 piece set bonus of the Raekor's armor set for Barbarian gives the Charge ability every rune:
But while able to play slightly with the possibility space of what a character is in Adverbs, no Diablo 3 character has more or fewer Verbs than any other - just different amounts of effectiveness of the verbs they have. Player Inputs (whether that's talent selection, equipment, or any other system) are not able to create a character that has 7 verbs, 7 limited adverbs, and 3 global adverbs, nor 2 verbs, 14 limited adverbs, and 7 global adverbs.
Obviously there is some great difficulty in creating good gameplay when you as a designer can't be sure of what gameplay verbs the player will actually have. For a game that has a broad audience, you need to structure your systems such that they produce compelling gameplay for that broad audience. And this post does not contain "how to draw the rest of the owl". But - I would be curious to see what games have experimented with not just interesting layering of limited action sets, but also limited action sets whose shapes are responsive to player choices.