My main character is a Weaponmaster/Fire Mage that's about level 75. I use a two handed sword as a weapon, and do all of my damage with melee attacks. I only use the Fire Mage aspect for Fire Shield and Flame Blade.
Really, that sort of shows one easy way to run a character. Figure out how you intend to kill things (in my case, with a sword). Pick a class that can do that. Then pick a second class that gives you some variety or flash or extras that you think will be fun.
The Weaponmaster is particularly good for that, because its got passive accuracy and damage bonuses and some cheap, efficient ways to hit things. You can combine it with anything at all. Want someone who fights in melee, but also has pets? Weaponmaster/Necromancer. Someone who fights in melee but has ice spells for utility? Weaponmaster/Ice Mage (use ice mage to slow enemies to defend yourself from them, ie, use the ring spell). You get the idea.