Live performance of 'Stranger Things' theme song played on hardware synths

I just finished Netflix's Stranger Things. I feel like I'm the only person who thinks it could have ended differently. And the explanation of some things are just so lacking. What is the monster? Where did it come from? Why did it want to take people and eat them or whatever? I really enjoyed everything about this show but I just wish it wrapped things up a little cleaner. Maybe season 2?