Hi Nigel,
Where are you going to be showing your gelding? In what classes? Breed big shows? Breed small shows? Open shows?
Who is going to be showing your gelding?
My mom really hates razoring (she would hate it more if she was the one doing it), but for the last Championship/World Show she asked me to razor her silver chestnut gelding. Some kids were going to be showing him (and taking him home after the show) and just razored he looked like he was wearing black make-up - and the kids stayed clean(er).
You have a pretty boy no matter what you decide.
Overall presentation matters, but at the end of the day the judge is going to pick the horse they like the best, not the grooming job. The flip side is true though, too. You only get one chance to make a first impression, and a good groom can make a good horse look great, and a great horse look so good that you can't take your eyes off of them...