It's good, the higher your level, the greater the magicka increase.
For instance, your first level up is when you reach level 2. So the leveled magicka mod will add x0.1 magicka according to your intellect. And you keep leveling, it will add .1. So by the time you reach level 30, leveled magicka will add x2.9 magicka according to your intellect. So if you have 100 intellect, and lets say hypothetically, the race you chose had no race-magicka bonus, then you'd have 100 magicka without the mod. With the mod, you get 100+290= 390 Magicka. I would definitely recommend this mod. I am not sure if it will screw up your save game though.