Well, playstyle-wise I often make my characters similar to myself, as the weapons I prefer in-game are the ones I have some level of experience with in real life, such as unarmed martial arts skills, a rod or a bow, although while I do have some experience in using a katana, I almost never use a two-handed greatsword and always prefer dual-wield, either daggers or swords. Axes and maces are too bulky for me. Also I like to play as either a thief-like character, ranger/druid or otherwise just DPS-ing with some CC added into the mix.
Appearance-wise preferences does shift with time, but at the moment I usually shift around, with a few preferrences. If I can play as some kind of beast race, I will almost always play as that, like the Khajiit and Argonians in ES. I pretty much always play as Sylvari in GW2, because I really like plants. Also the female Sylvari player character is voiced by Jennifer Hale, and that should speak for itself.
Lastly, I always play as a female character, for three reasons: 1: As I am a girl myself, I feel most comfortable playing as one. 2: Female characters usually have better voice acting for some reason. 3: I detest bulkiness, especially in armour and weaponry. Female armour, regardless of skimpiness level, is almost without fail a LOT less bulky than male armour, especially in fantasy scenarios.
So to conclude: While some of my preferences are based on me and my own abilities, I do like to switch around and make different characters appearance-wise, but I have a fairly solid playstyle that I'm comfortable with and rarely deviate from.