I really like this pattern, white top and bottom, main stripe one color (which is actually two gel selections), and the back / lower stripe a second color.
Clean, simple and will look good a long time.
I like blue or red for the main stripe and silver or gunmetal flake for the back stripe, kinda opposite of this boat.
Metalflake is good.
Interior light grey base w dark grey and/or color accent to match the outside.