Character Archetypes (Or What You Require in a Character)

Some of the people i play lots of games with tend to play similar characters.  Some always want to be the pretty, smart girl, for example, or the biggest-toughest tank.  Still others might have characters that seem to have nothing in common at all, except that they all have extensive backstories rooted in a dark past or a volatile home life.

A lot of people will say 'i never play the same type of character twice' and be very wrong and/or lying about it, but i've probably played 50 different characters in less than three years, and i do think i've done pretty well at keeping them all new and fun. Of course there are some recurring patterns, but i like to think that even within the same archetype, they're each different enough to at least show i've made an effort.

 My personal requirements for any character, for any game, with any group of people are as follows: he or she must be able to survive the setting alone (through skills and/or fighting ability), but have a reason to work with the group anyway--and it can't just be something like 'they asked me to' or 'the same guy hired us.' There has to be some inner drive to work with someone else, even if there is reluctance involved. I don't think a GM should ever have to beg or coerce people to go along with a group--that's up to the players.

The male characters i play have the most in common: they are all tall, dark, and stoic. It doesn't matter if he's a werewolf, a ninja, a gunslinger, or a gigolo: he's going to be tough, confident, and to-the-point.  I surmise that this is probably because i'm a chick, and i want to play my ideal or whatever.  There might be some deeper psychological issues at work, but i think this theory is direct and logical enough, so let's move on.

The only thing my female characters seem to really share is a very deep, extreme, stubbornness. My women are definitely more varied than the men; they range from a 15-year-old Buffy-style Slayer who just-wants-to-kill-stuff-and-to-hell-with-the-consequences, to an immortal Japanese Samurai who feels she must atone for past indiscretions, as well as prepare her younger teammates for battles yet to come. I play women that are big, small, tough, meek, muscled, and deceptively frail. They're outspoken, shy, vengeful, peaceful, and everything in-between. I don't even mind playing ugly and/or fat chicks--i mention this only because it seems to be such a rare position on the matter.  I've seen people (men and women alike) cheat just to boost their attractiveness scores, and calling them out on it tends to be very...well...ugly.

So how about you?  Do you favor any particular archetype in your games?  What qualities do the majority of your characters have in common?