Mastering Magicka
BETA Release 12a

A spellcaster's proficiency with Magicka increases as they advance in the various schools of magic. Maximum Magicka increases as more skill is invested in the various schools of magic (up to x3), and spells become cheaper to cast as a spellcaster advances in the school of magic that governs the primary effects of the spell (up to 50% cheaper).

Magicka regenerates at a modest rate governed by one's Willpower and maximum Magicka. Those under the sign of the Atronach, or stunted Magicka effect cannot regenerate Magicka. Casting spells will stop magicka regeneration, adding a cast recovery for magicka regeneration.

Casting spells now cost Fatigue as well as Magicka. Fatigue costs are a constant cost regardless of the Magicka cost. Powers do not cost fatigue if they do not cost Magicka.

Armor now affects spellcasting; Magicka regeneration rates and casting fatigue is affected by equipped armor. Proficiency in the armor skills offsets the penalty, however unarmored will always prove the most effective. Bound armor is unique in that it is not affected at all by these restrictions.

Investing in unarmored will provide a dodging bonus, along with further reducing the effects of fatigue on spellcasting and cast recovery while unarmored. Acrobatics also provides a dodging bonus while unarmored and in light armor, but does not provide any spellcasting bonuses. Unarmored and Acrobatics bonuses will stack, though capped at 30% dodge bonus.

If using MCP's casting feature, a character's stance effects spell casting. Casting with a weapon in hand will increase casting fatigue and cast recovery delay, while using the casting stance will decrease both. This adds a nice feature to this option.

Download at Morrowind Nexus: http://morrowind.nexusmods.com/mods/42269
Requires Morrowind, Tribunal, and Bloodmoon.

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The goal is to make spell casting a more dynamic and immersive experience. Maybe I succeeded, or maybe not. Either way, let me know!

Next update will be a new version of the Armor module; here are the plans so far:

Magicka regeneration penalties and spell siphon (spell cost reduction) penalties are now a constant; armor skill cannot affect them. This will make the armor weight class a noticable factor in spellcasting. These are physical properties of the armor weight class that skill cannot overcome.

Casting fatigue however is factored into armor skill, and 100% of skill invested will negate any cast fatigue penalty for that armor weight class. Cast recovery is no longer affected by armor.
Light and medium armor are only half effective with magicka regeneration from willpower and spell siphoning. Both increases casting fatigue by 50%.
Heavy armor nullifies magicka regeneration from willpower (so only base regeneration occurs) and spell siphoning. Casting fatigue is increased by 100% in heavy armor.

Acrobatics will provide an evasion bonus unhindered for unarmored and light armor slots (up to 20% at 100 acrobatics), and will be half effective for medium armor (up to 10% at 100 acrobatics). Heavy armor will only be 1/4th or 1/5th effective for acrobatics evasion (so a maximum of 4-5% evasion at 100 acrobatics).

Unarmored will provide an evasion bonus for being unarmored up to 20% at 100% skill. Unarmored will also decrease casting fatigue, and also decrease cast recovery, and doesn't hinder magicka regeneration or spell siphoning. Any armor will nullify the bonuses per slot.

Unarmored and Acrobatics evasion will stack together, to a maximum of 33% evasion total.

Of course, bound armor is treated like unarmored, so it enjoys a unique status among armor.

This sounds awesome!

Is it safe to install midgame? Also, do you have any plans for NPC magicka regeneration?