Currently, this is what I have decided on my drama rating system. 

★★★★★ Masterpiece. One of my absolute favorites. I will never get tired of rewatching again and again over the years.

★★★★½ Superb. I really loved it. Up there with the favorites. Will watch it again, when got nothin to do. 

★★★★   Solid and good. Worth a try, watch at some point when you don't have much else to see. I would recommend it to others.

★★★½  Decent. Not bad u could say.

// You would not see any dramas with the ratings below in my list. If u see any dramas with ratings below than the above ones then it's just awful.

XD

Have A Great Day!!