I like to change it up from character to character. The first time in Inquisition I was very aloof, smart, and pragmatic. The second go around I was more sarcastic/funny. The third I was more aggressive and exacting. My latest one is a bit of a mix of the last two. I almost always play myself the first time through, though.
First time I play new games I always choose the lawful good style. Not hurt any feelings, always be on the side of good, things like that. I choose the romance option wherever possible, of course. On my second playthrough, I go the exact opposite route. It always makes me sad, but it has to be done. I don't want to move on and ask myself "What if."
I always try to be nice and hear the NPCs out. So I am almost never aggressive, unless the NPC has wronged or provoked me in some way. It could also be said that I am a bit manipulative, in the sense that I approach them depending on how they want to be approached (sarcastically, realistically etc) in order to get the most out of the dialogue and make them like me.
I like sounding like a smartass in games and it's even more hilarious when I'm facing bosses. I think that's why I tend to like Dragon Age 2 better since it gives me the option to have my character be a smartass in every interaction.
First playthrough I try to be good and honest, pretty straightforward gameplay. The next time I would go sarcastic and devious, basically not giving a fuck what I would say.
During my first playthrough, I always respond in the way I would in real life. It all depends on the situation. Generally I am nice with a bit of a joking/sarcastic side, though I can get very stern when the situation demands it. I have a lot of fun seeing how the characters react to the "real" me. After my first playthrough, I will switch to an all-"good" or all-"bad" talking style to see how things go.
I try to go with what feels best. My character is always one of the "I wish I wasn't part of this, but I am, so I'll help the best I can" types. Though I have picked options that sounded menstrual, but ended up being aggressive.
I can never bring myself to go the evil route so I'm usually your standard goody two shoes. I also like the humurous options as well.
Usually humorous / sarcastic ones. I like playing bad guys occasionally, but I find Bioware's options are more aggressive than I would like. Not every bad guy is automatically a crazed barbarian. A halfway between sarcastic / humourous and evil would be nice.
I'm usually choose the reassuring/good/ supportive dialogue. I think that's how I am in real life, so I usually play that way in games. I try to play more of the renegade type but I just can't do it. I know it's a game but something within myself can't choose that route. I will sometimes choose humor but for the most part I try to be supportive to my fellow companions. Whenever they ask me to go help them with mission, I always agree. I never say I don't have time for this. Maybe I'm a bit of a push over. But that's the way I play these games.
I feel abit silly saying this. However, I sometimes make "good" characters or "evil" characters. I choose choices according to how I feel they would behave doing or saying certain things. In a way i'm playing as someone rather than it being me.