Many of the systems in DH2 end up giving the players some time on their hands. Especially warp travel. So instead of coming up with a problem on the ship to solve all the time do you guys have a system of downtime activities that you use? or do you let the characters come up with something to pursue? I'm thinking of making these down times as the only times you can spend xp that way it gives very easy material to come up with what was done in the time. However if there's no xp to spend then that leaves basically nothing for them to do if they can't come up with something.
So I was wondering what you guys generally did.