D Rio O.
Yes, it allows time to reflect on the day and reset for the next. It relaxes the body and the mind ready for sleep. This let's the body use the sleep and wake up refreshed.
Yes it's good to do yoga before going to bed because it helps you calm down and see reflect back on what good things you have done in the day and all the bad things you're done.
Slow yoga helps. Pranayama is yogic breathing thats great too. Try holding each pose for 5 minutes, and make sure you can breathe deeply and easily, or adjust the pose until you can.