Window Tint

Hey all, I have a black 2003 Civic EX coupe, I am looking at tinting the windows, but there are a few questions I have. I know there is no real rules for the back windows, but the driver and passenger in front must be at 30% visibility. I am not for sure on the numbers so bare with me. What in your opinons would look the best for tinting all the windows? Should I completely black out the back windows, and the full amount on the front ones. Should I go a pinch under legal on the front windows? Should I do all the windows at the same darkness? Tell me what you have seen and prefer, Thanks.