I just had a thought of a cool feature for lost mode. So after your phone is stolen, thieves will turn it off most of the time. This leaves find my iPhone unless as it will never find a phone that is off. My idea is if you can report the phone "lost" on iCloud before the thief can shut it off. My idea is that after you activate lost mode the phone screen will not turn on and phone will not vibrate or make a sound. Essentially the phone is turned off and shuts down all processes other find my phone (save battery). This makes the thief the phone is turned off but it really is not. The phone can be tracked during this time and hopefully increase the recovery.
After the phone is recovered, just go back into iCloud and turn off lost mode to use the phone normally again
After the phone is recovered, just go back into iCloud and turn off lost mode to use the phone normally again