Multiple Magick Bars with their own Regeneration rate and use. I was thinking of several different versions, and ideally all would be implemented in the same mod but highly configurable. I'll take what I get though. Frankly pure Mage playthroughs are tough, especially at the beginning, or when using difficulty/overhaul mods. Until you get OP. This is set to switch things up.

You can set it up so that your Magicka is split between different Factions. The Factions can be anything from Spell School, to Left/Right Hand, to just 3 Seperate Bars. I'll elaborate.

Imagine if you had a Magick bar for each spell school. It would give you a good reason to diversify, since running out of Magick for Destruction would still make Conjuration viable mid-battle. Plus, summoning or buffing yourself with Alteration won't reduce the number of Fireballs you can shoot. It may seem OP, but when you setup Skyrim with increased spawns, you don't want to chug potions all day, or be useless without them.

The Left/Right hand isn't my favorite, but you can make it. It'll even be lore friendly with a little background. "A mage discovered that magicka coming from within shoots up from your toes and down from your head to your fingertips. By separating the 'flow' you are able to double the..." yatta, yatta. I mostly listed it for diversity's sake, and in case the other two don't work.

A separate Meter(s) that is tacked on the front or back of your "default" Magicka Bar, with it's own logic and functions. For example, you could have a larger bar that regenerates very slowly on the "front" of your Magicka Bar that is used up first. So if you take a long time between fights you can get a breather and have more Magicka to tap into. Its kinda like the "Traveler's Magicka." A logic you could put on this Faction would be to instantly deplete when combat starts, making it ONLY suitable for traveling. On the other hand, you could have a Faction BEHIND your default Magicka, making the meter small, but increasing the Regeneration Rate to extreme levels. This would be a combat Magicka Faction, suitable so that even on your last leg, you can cast the simpliest of spells to keep fighting, making "weaker" spells useful in late games.

The reason I wanted the customization would be so that people can come up with their own Factions and put logic behind them. Like having a meter available only when you're on low health, after you kill X amount of people in X time, a "Rage Meter" styled one, or even have meters designed around which Race you are.

I'll leave the rest to your imagination. Thanks for reading through.