In most game systems there are character classes. They are mostly rigidly outlined with specific purposes and functions, such as the fighters who fight, the rogues who steal about, and the wizards who cast spells. Most people who play also generate these characters and play them as written. Armored fighters attacking the enemy, thieves back stabbing, with magi casting spells from behind. The word stereotypical leaps to mind, but many don’t even think about using the classes in other roles.
Think of a militant mage, sitting in a castle, designing spells that make him a killing machine, clad in magical armor and an aura of energy that flays the flesh off his enemies before they even get close. Or a spell that creates a small (or even large) army of magical warriors that obey his commands and fight for him. That’s just one option with two different possible variations.
Given that example, take a moment to think of what character classes actually are. A class of person, say, upper class, does not always mean a wealthy old white guy in a suit smoking a cigar in a high back leather chair. There are a wide range of reasons to be upper class and as many different types of people in that class as there people in that class. It’s the same with the character classes. There are ranks of fighters, guilds of wizards and thieves, and cloisters chock full of clerics, but each one is an individual who should be given the same individual attention as one would give a character in a book or story. Use your imagination and make that next character using enough mental and imaginative dexterity to dodge that cookie cutter.