I like entry #4. Please keep trying to come up with creative ways to enhance the up. You can look at the other entries I've ranked to get a feel for what I like so far. Anything with an arrow pointing up or just the word up enhanced are good.
I really like 19. I ranked it #1. Can you create a few different color variations with the same design as 19? Keep the colors the same in general, but just make the gray lighter and or darker and the green lighter and or darker. I think this design is a winner. Thanks.