As a DM I've not run anything by myself, but have helped out co-DM ing a bit. I'm not experienced in building or scripting.

As a player, I generally stick to neutral or good characters. Nearly all of my characters are flawed in some major way, and often through various tragic events in their background. DMs will always have a variety of choices and development options based on my biofiles.

Most of my characters carry over some part of me, often because this makes it easier to play the character consistently.

I rarely play out things because of character's alignment preferring instead to base actions on what is appropriate according to the character's biofile.

When making a character I create a personality which I can relate to first, and which I think will be interesting to play. Then I decide the most important events in their lives.

After this I decide on classes and skills for the character, and go searching for a portrait.

As I continue to use the character, I will write lyrics/stories, side-adventures and so on. I very much prefer campaigns where I have creative freedom, and where the campaign revolves around the characters.

I'm fine with the DM making the setting, but as a player I want quests centred on the characters as much as possible.