How about going to the tropics this summer? This picture is from my trip to Kauai. Be creative with this one: maybe change the colors of the sunset, maybe change the trees from a silhouette to back-lit color, maybe change nothing; do whatever you want! Just have fun!
Where they would be very dark, but not a silouhette (still having color, just very, very dark colors) often lighter near the edges of the shapes or having large areas of dark and light tones with very little medium tone.