I tend towards the magic users.  I like their multifunctionality and mystery – which I play pretty well according to the lamentations of my old gaming pals.

Thieves and Rangers after that.  I liker a character that can do more than just swing a sword.

I tend to play mostly fighter types. They're simple in both roleplay and mechanics yet diverse enough to cover a wide variety of fighting styles and cosmetic options. The latter point explains itself in terms of how objectively important it is, but roleplaying ease is more subjective, and as such more important in my case. By "Roleplaying Ease," I'm not necessarily talking about making simpleton-type characters, but rather, making characters where it's easy to roleplay in terms of making decisions that your character would realistically make.

What I'm talking about is basically the reason for which I NEVER play Tactical/Resourceful/Insightful Warlords in DnD 4e. For those of you who don't know, a Warlord in DnD 4e is basically a leader who leads his/her allies through strategy and inspiration – basically a field general. I am not good at all when it comes to strategy and tactics (I tried reading Sun Tzu's Art of War to fix this, and it didn't help). But whenever I see anyone play a Warlord or other "smart" character, it's assumed that because the character is "smart," the player will make his/her character do "smart" things during roleplay.

The problem with this assumption is that the way the character is roleplayed in this regard depends on the player's abilities, not the abilities of the character itself. The fact that your character has an 18 (pretty high for a starting score in DnD) or so in Intelligence or Wisdom or whatever has no reflection on your ability as a player to emulate those abilities for yourself, and if you as a player are not "smart," you can't think of doing the same things that a "smart" person would reasonably think to do, and if you can't think of doing a particular thing, your character will not be able to decide to do it.

Sorry for the tangent. My point is, I'm not "smart" in terms of my ability to make wise decisions, and that's why I make characters that rely more on raw power than strategy; hence, fighter-types.