Your playlist is the heart and soul of your station. Unless your station is a news station or has a no music format, your playlist is your station’s heart and soul. This should flow like a surfer over a wave, have you seen a surfer? They don’t just go straight to the shore; they go up and down and sometimes with one or two tricks. The same should happen with your playlist. If you play your 10 best songs one after the other the same hour you will run out of gas for your next hour. What are you going to play the next hour? Your listener will leave because they already heard the best you got.
My recommendation is to split your music in groups for example:
Dividing your music like this you could cover one hour playing 3 or more songs per group in one hour and still have gas and variety for the next hour. Usually you can cover one hour with 15 to 20 songs, it all depends of the length of the songs and if you have sweepers and jingles between the songs.
Remember see your playlist as a rollercoaster; it has to have ups and downs to be entertaining and fun.