The Black Ring are the toughest opponent type in the game, tough enough that even facing them at level 34, when they're level 28 can still be dangerous.
My advice is to drink your buffing potions, and try hit and run attacks. Points into vitality might be helpful as well.
I'm not sure that it's a great idea to use Magic Missiles with a melee-focused character. Magic Missiles are meant for a caster, it's the weak spamming spell they use to keep dealing damage while they wait for the cooldowns on their main damage-dealing spells to wear off. The key word there is WEAK.
For a melee-fighting hybrid, you want to use any of the other three offensive skills - I recommend Firewall, which is a perfect spell for a fighter-mage, it hits everyone in a short range around you for heavy damage, making it perfect for fighting in melee.
I hope you didn't put in a lot of points into Mana Leech and potion efficiency. Or Magic Missile.
I also hope by "fairly balanced" stat set that you aren't trying to raise Strength, Intelligence, and Dexterity by the same amount. Especially Dexterity, don't put points into that one at all.
