I love the 3e multiclassing rules, so I don't think I've ever played a straight character class. However, every character I've played always ends up having at least a few levels in some spellcasting class.
Presently I play in 2 games. In one I'm playing a level 3 bard. In the other I'm playing a fighter4/sorcerer 2. She'll level up next session, which is Saturday, so I need to decide which class her next level will be in. Fighter probably.
But as I said in the thread about races, I usually DM.