One of my players is playing a lashunta envoy with the death-touched theme. As such, they have access to "Detect Thoughts" once per day.
To give a little flavor with their theme, I decided to let them use detect thoughts on only the dead and dying, instead of on anyone alive. In the case of the dead, the thoughts would reflect their last moments, and they have to have died in the past week.
How unbalanced is this? What should I be concerned about? If it matters, we're running the Dead Suns campaign.