Have you tried the priority notifications settings already included on your phone?
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.
I have tried this and it works to a point. The issues is the vibrate options on the phone seem very limited (short in duration) and I don't always notice them. I was thinking an APP may have better options
I have the same problem with the vibration/ring duration. With past Galaxy phones, the number of rings could be changed. With the S7, the number is set and can't be changed. Because of this, there are times when I can't answer the phone before it goes to voicemail.
You can give this application a try or others like it. Light Flow - LED Control - Android Apps on Google Play