The way it is supposed to work is to simulate having to earn your Magicka level.
Normal people have no or little Magicka. If you are gifted, you can set a starting amount.
However, when you get hit or are near death, the amount of Magicka you have at your disposal shoots up. Very close to death gives you a boost that could even be overpowered.
This is to simulate instinctive reactions for survival (think, Mutant stories like the X-Men).
As you practice Magic through spells, enchantments and alchemy, your base Magicka will increase.
That includes the number of potions you drink, ingredients you taste, books you read... not a single time but overall.
About potions, you will notice a blur effect when you drink too much. That a blinding headache from potions being toxic.
The more you drink and practice spells, the more tolerance you build and the longer you can go before getting headaches.
The main quest about going under the apprenticeship of Farengar is a way to give you gradual powers through practice and learning.
Part of the story is to get you to tap into the effect of crystals (Skyshards here) to focus your powers.
The story is not yet finished but it will take you from simple apprentice to the depths of the Midden in Winterhold's College.
I use that system all the time now and I call it balanced most of the time
It is a blast to find out in the heat of battle that you can suddenly cast a dual blast of flames powerful enough to knock a Mammouth if timed right.