Thanks for the quick response! I'll try to explain the second part better.
Right now, after drawing up at the end our turn, our hand looks like this:
|_|_|_|_|_|
If there were a way for me to preselect cards that I *would* discard if I had to:
|_|_|D|D|_|
Then once a militia or Goons is played, my opponent wouldn't have to wait for me to choose. If my selection depends on what my opponent does, or I want to wait for some other reason, I wouldn't preselect, and I would be prompted as normal, but most of the time, my choice of discard is completely independent of my opponent's other turn actions.