About the colorcoding: As colorcoding is information, and information is usually a good thing if, I would absolutely vote for colorcoding. My preferred combination would be greyed out for exhausted topics, some color for the list of topics on quest related dialogs as suggested by Paterik and also as Stabbey mentioned some kind of easier to read colorcoding regarding the player char dialogs.
I also like journals where the dialogs keep noted, at least the quest related ones.
An option to increase the height of a chatlog would also be cool.
OT: Did I ever mention Kingdoms of Amalur and Divinity 2 are my absolute favorite RPGs four hundreds of reasons? ^^
