If you have all perks in Illusion that relate to increasing the power of your spells, are they strong enough to fight enemies that scale to you at level 60-70 or above?

Thanks.

I believe that with all the perks and dual-casting your spells they will affect everything that does not already have a natural immunity.
I am not 100% sure but I think the master spells don't work on everything.

Also, referring to expert spells and only one hand. :S?

With one hand? the answer is no. Dual casting the answer is yes as it multiplies the effected level by 2.2. Which with the other perks will put it over the level cap for most every enemy.

I got a few questions for you.
1) What is the level cap for enemies
2) If dual casting I get 2.2 should I skip the master level spells or do they also gain 2.2 with the perk
3) Do I need to pick up perks like Rage and Kindred Mage to be able to hit the enemy cap or can I hit the cap with only kindred mage