How about improving dialogue system by making it unique and more interesting?
I think a real-time dialogue should be implemented in the game, that is to say, while you are talking someone the game moves, people move, people die, people run...
You point to a NPC and then you press the "talk" button.
It could be a way to improve realism in the game.
Also, the ability(In terms of being able to "talk" faster) to speak(With a microphone) and say the available dialogue options.
For example, you could personalize your voice commands to say "One!", "two!"...(Or "Good bye" to leave the conversation, "No" to general negative questions...Considering ordered dialogue options.) To choose one of the dialogue options. It could be easily implemented.
These commands could be also used to give orders to companions.
What do you think? Am I completely mad?