Sidequests and character input...

I have noticed something really nice while replaying the game. When you talk to NPCs and accept a quest, some characters are more interesting to use than others. I don't know if things are random when it comes to affinity (so I won't get into it), but if you pick the right character, he/she will personally get involved in the discussion, making you learn little stuff about the character that may not be revealed in the main story.

One little example with Dunban. There is a drunk nopon in Alcamoth and, if you main Dunban (or have him in the current party at least, I don't remember if it's a requirement to main him) to talk to the nopon, Dunban will reveal that he used to have problems with alcohol.

Considering the numbers of quests and that you have 7 characters to choose from, it's easy to miss "interesting" character information (maybe even interactions). So, I wonder if we could share those here ?
I know, for example, that Sharla often gets chatty about quests that have to do with romance. I have another with Seven

Spoiler:

Yes, I love that feature about the quests in this game! (I think the party member in question has to be in the lead for the extra conversation to happen.)

The quests on Xenoblade Wiki all indicate which character gives extra comments on each of the quest's Wiki entry.

^ That I need to check. I played it many times and always walk around to gather and finish quests with character I need to rise his heart-to-heart with other party member.
I knew that special conversation show up when you take tree skill quest. That show that you need to finish game many times and there is still something new to discover.