Yes....your magic regen can get better with proper enchants but unless you use exploits your mage will eventually be alot weaker then other classes at the same level the higher you get. I use robes in true mage style so I get rocked by most enemies and I'm lvl 30, it's challenging but frustrating that my destruction spells are getting weaker as my enemies grow stronger...I've had to resort to using 1h and archery to compensate for the destruction being broken (it doesn't lvl up with you as does every other skill).
I've noticed how certain enemies I encounter are near impossible with my mage but are a breeze with my 2h warrior nord of the same lvl....fact is the mage is a 2nd class citizen to the warrior in skyrim.
you can buy a master robe of destruction, a eminent helmet and ring of destruction, and craft a amulet of destruction and at least get one field of magic super low cost, lets say destruction and thats with no exploits, its a game mechanic to reduce magic cost, the fact you can reduce one field of magic by a few more percet by using enchanting is very insignificant, and the problem with magic is it doesn't scale, it lacks some oomph and magic regeneration is slow, but dropping a field of magic cost down to 80 or 90 % isn't an exploit since its part of the game design to be able to do that, and even at that, thats only one field of magic, you don't get to lower every field of magic down to zero%, so as a mage i use all fields of magic and sure i make sure the destruction magic is low cost cause i use a lot, but when i cast an alteration or illusion or conjuring spell, it uses up magic reserves plenty so these so called "exploits for magic are totally over exaggerated. reducing magic cost isn't an exploit at all and thats like saying using heavy armor or potions or bows which do incredible damage is an exploit, magic isn't balanced well. but its still fun to use. if you don't just rely on one field of magic.