My characteristics. I mostly play on huge with 18 or 14 civs and have spacerace victory enabled. I like wars but usually won't start them myself.
Caesar, Alexander, Peter: Opportunistic warmongers, they usually know who to pick on, create large empires but fall short scientifically to compete for the spacerace.
The Indians, Americans, Germans and English. And Cyrus i suppose. Quiet laborers who all are able to win by spaceship victory if left alone and given some room to expand. Ghandi is a natural target for the warmongers but he can bounce back from seemingly hopeless situations. All of this group are pretty tough, can survives bare periods and suddenly reappear.
The loudmouths: Catherine, a lot of potential but always taking it just too far. As do the Mongols and the French. They just miss that instinct for a successful campaign that the warmongers have. Maybe the Chinese belong in this group too. Getting too cocky when they seem to be running away with the game.
Saladin, Montezuma and Huayna Capac. Rulers of the early game who don't seem to know how to follow that up. Maybe they pick the wrong friends. And the latter two definitely pick the wrong enemies.
Mansa Musa. He's a bit of a loner. I like him. Suddenly appears to have some advanced techs noone else has. he's not tough enough for this game though (as am i).
Hatshepsut and Isabella. One trick ponies, which they sometimes pull off. Hattie with a smile, Isabella with her zealotry. I have a soft spot for Hattie. And with the assurance that she won't be able to sustain her blitz start i'll allways throw her some goodies, she's rarely less that pleased with me.
Leaves just the king of the game: Tokugawa. As stubborn as they get. I played a noble, standard map with 14 civs with the sole intention to be his puppet (character name: Tokugawa Rules), allways give in to his demands, adopt his religion and civics. And wonder, he was my closest neighbour. Well, it was actually a very boring game. I had a good starting position, took a commanding lead but his stupid mercantilism (prepatch but i doubt it's much better now) cost me dearly. I observed a bit what techchoices he made but it looked all very random, i think he completed the Sistine Chapel. During the space race he dragged me into a war with the leader, of all people, Hatshepsut. Louis XIV, our mutual neighbour, with whom he had very good relations, quickly jumped in on me. I overlooked a fleet of gunships and my capital, with several wonders, was taken and all my land pillaged. I managed to recapture it and force peace with Louis. I fooled on a bit, gave my capital to Hatshepsut for peace, the next turn Toku took it

. He then taught me a very useful lesson, let a city surrounded by hostile culture die to level 1 and build it up from there, in no time it was 50% Japanese. He's still my hero.
Phew, that was a lot longer than intended. Sorry.