Using MP universally, or strictly for magic skills

I find that RPG combat tends to work best with at least 3 resources (and generally no more than 5 resources), with HP, MP, TP, SP, Cooldowns, ATB meter, Limit Break meter, and so on all counting as resources. (The exception is Action Battle Systems, where it can work well with as few as one resource, HP.) Having at least 3 resources enables a lot of Incomparables, interesting tradeoffs, and differing priorities and different points within a battle.

So with that in mind, I might ask - what resources will Physical Combat-types use if they're not using MP? If there are other systems that gate their skill usage or give them interesting gameplay on their own, you can probably get rid of MP for those types (just be sure there's not a huge divide between the resource-neediness of mages and the resourceless, always-consistent nature of physical-types). If you don't have any of that, I wouldn't recommend removing MP from physical-types "just because MP doesn't make sense for them".

 

My game has few, if any, physical techniques that are not Limit Breaks. Most of them are in the arsenal of the Thief and Ninja classes. Ninjutsu, however, is explicitly quasi-magical in my lore and uses elemental powers similar to those of the Battle Mage, so it is OK to use MP for ninja skills. Thievery is the only skillset left that is not magical in itself but inexpicably uses MP. I chose to ignore this little inconsistency.

 

I added the ability to my Frog Health plugin to customize what each class's HP, MP and TP stats were named and abbreviated. So everyone has MP but it can be configured for mages to remain MP while a barbarian has RP (rage points) and fighters can have SP and so on. It's just flavor but helps.