Showing is all about judges perspective. If you get a judge that likes there cobs evenly marked then that's what they will place high.
If they like there cobs unusual then that's what they place higher and you do well. How old is he? Are you planning on doing any ridden with him?
He looks quite fine, so would be better plaited and trimmed up! Do you jump with him? If he has a nice jump he might do well in working hunter classes? You can always show him in genetic classes such as best gelding / family horse / judges fave etc.
I was at a show yesterday where a badly behaved horse turned out incorrectly was placed higher then a nice little horse with correct confirmation who was quiet and obedient because the first one was the same type as what the judge shows herself.
One day you can clean up and the next day you can come bottom of the Lineup. Don't worry so much about "if he'd do well" and just have fun