Right now, martial builds rely too much on INT—WIS to an extent as well—to ensure success because they have to make certain they have enough maximum mana and mana regeneration to use their martial abilities alongside having enough CON to stay alive (which includes fortitude), enough STR/DEX/PER to deal sufficient damage with the appropriate abilities and weapons, enough DEX for attack speed or evasion or lockpicking, enough PER to increase their critical chance and detection, enough WIS for additional maximum mana or willpower, and so on.
Depending on a player's build, many of these attributes can become "dump stats" except INT, and the only attribute that should be reconsidered being a "dump stat" is CON as that attribute is what determines how much a character can endure before they fall—especially in PvP. While I love in-depth options, options, and more options, mana management shouldn't be an issue for martial abilities because they're not magical. You simply swing a melee weapon in a specific fashion that requires only the physical prowess of its wielder, or you fire an arrow in such a way that requires critical thinking and eye-hand coordination from the (cross)bow's wielder.
These abilities should be governed by a resource known as "Stamina" instead of a mystical resource normally used by the manipulators of the elements.
Above, I made a rough edit to the resource bars to show how an additional bar for stamina could look.
Stamina could be governed by both Dexterity (DEX) and Strength (STR). Dexterity could add 100 points of maximum stamina while Strength could add 50 points of maximum stamina. Stamina regeneration could be completely independent from those attributes in a way that it could regenerate faster on its own and much faster out of combat as fixed values—possibly altered by abilities (such as buffs), talents, equipment, and enchantments/imbuements.
If stamina regeneration must be tied to an attribute, the same philosophy could be used for Intelligence and Wisdom as in Strength could affect stamina regeneration like the former does for mana regeneration.
Martial abilities having their own resource would help all builds, that focus more so on melee and ranged (physical) than magic, be able to better consolidate their builds by eliminating their need to spread their Attribute Points so thinly across many they normally wouldn't normally need unless they're trying to become hybrids. If they do wish to become hybrids, they would have better control over doing so as all martial and magical abilities would have their own respective resources.