Certainly. "Thoughtful", no matter how defined, is a function of the users. To me it means something very different from the majority of contributors here, but I suppose it's neither my nor anyone's place to say what is or is not, since we're quibbling over definitions. I think most active contributors here use "thoughtful" in the sense my wife or mother would use it vis-a-vis, say, a thoughtful act. That's fine, IMO, but not something I'm keen to jump into most often. You're correct in that no matter what features and functions exist, the timbre of the site is dictated by the culture that has evolved (and continues to). I'm not sure one could design a mechanism (or if it would be desirable) that encourages a specific cultural bent.They just aren't exactly in line with that goal of "thoughtful" discussion.