Todd talked about "Spreadsheet Magic" once and how he didn't want the player to be doing it. What good is not having the player do it when the game dev doesn't do it either?
Here's that tally of Ways To Boost Damage that I talked about earlier...
Non-Destruction killing implements get the following methods to increase damage:
* Weapon material tier graduation (Iron -> Steel -> Orcish etc)
* Power attacks
* Smithing
* Direct weapon enchantment
* Indirect skill-boosting apparel enchantment
* Alchemy skill potions
* Basic skill increase of the weapon's associated skill (or "Kill Skill" as I call them)
* Root perk tree perk graduation (5 perks for up to 100% boost for all weapons covered by that kill skill)
* Critical hits (applicable for just bows and swords... but also broken in Vanilla IIRC) or bleed effects (just for axes)
* Sneak attack bonus (up to 4x for bows, 6x for onehanders, and 15x specifically for daggers and the un-perked 2x for archery and 3x for onehanders is nothing to sneeze at either)
Ways to boost Destruction damage:
* Higher tier spells (which has the drawback of increasingly inefficient damage/magicka cost ratios)
* Dual casting (which only boosts overall damage compared to double-barrel single cast by 10% for a 40% increase in cast cost)
* 6 perks to get a total of 50% increase across the board (compared to 5 for 100% for the mundane kill skills)
* Aaaand for the only one that isn't drawbacked or inferior to counterparts... Alchemy skill potions.
* NOT rote skill increase
* NOT direct enchant (nothing *to* directly enchant!)
* NOT indirect apparel enchant (instead we get paltry cast cost decreases unless you cover yourself head to toe and/or grind Enchanting)
* NOT sneak attacks
* NOT critical hits
* NOT smithing (just like with direct enchanting, nothing to craft on)
I omitted any boosts sourced from unique items (like the DB gauntlets' sneak attack boost or the Solstheim Dragon Priest masks) or special case effects (like silver on unnaturals). I may have missed something as well, as I am not making any pretense that it's comprehensive.
Will the exorbitant and inefficient damage/magicka ratios for Expert-and-above spells be addressed in your mod? The sheer hit that the Expert-level heavy missile spells do to the magicka bar makes them useless since the Apprentice missile spells are at the peak of the damage/magicka cost efficiency ratios (all other factors being equal), even comparing dual-cast Apprentice spell to single-cast Expert spell. Runes and AOE spells have justifications that they're AOE (and proximity explosive in Runes' case) for their drop in efficiency... but Expert Missile has no such excuse for the sheer drop in the efficiency.
Master spells are right out useless (or highly situationally useful for Lightning Storm's case) because of their downright abhorrent inefficiency, and for less quantitative reasons too: they root you in place and take a long time to build up to cast, depriving you of a key advantage that Destruction has as a ranged kill skill over Archery: mobility (at least until the Ranger perk gets involved) and making you highly vulnerable to melee people closing to http://tvtropes.org/pmwiki/pmwiki.php/Main/SquishyWizard range. This aspect is what makes the Firestorm and Blizzard spells practically useless, since they do not have the projective reach of the Missile spells or Lightning Storm (which is kryptonite to dragons almost as badly as Dragonrend is simply because it's hitscan and far-reaching).