Don't forget that as your skill in the magic school of the spell in question goes up, the casting cost goes down dramatically.
My mystic archer is a Bosmer with mage birthsign and has plenty of magic. She could get items to boost her magicka, but doesn't find that necessary. And she casts some pretty impressive combination spells that may, for example, immobilize her target, weaken them to poison, and either silence them or inflict them with soul trap (depending on the target). The poisoned arrow that follows is usually fatal. Her pool of magic has never been a problem. If it occasionally was, she would chug a potion. If it routinely was, she would grab a boost magicka item.
Ah, I thought as much, when seeing a skill that costs 600 magicka I was like O_O
I know at higher lvls there are sigil stones with +50 Magicka and such, but what about the starting lvls? (or is it not as important that early?)
I also saw that paralyze is the most magicka costly spell in the illusion catigory, like how much so xD?
Im wondering if picking the theif birthsign instead of the mage would make my character not able to use certain spells.
And im still stuck between Mysticism, Restoration, and Acrobatics for my my last major skill D: