A lot of male dogs pee on their front feathers–it is just one of the hazards of having a long haired breed that is actually quite small and close to the ground–there isn't much room for maneuver! :lol: His coat probably is not going to change much if you have already shaved it at a groomers in the past –breeders regularly say that if you shave down the coat it permanently alters the texture of it in many cases and it sounds like that perhaps has already happened?
I have neutered males as does just about everyone I know with cavaliers, and it is made no significant and in most cases, noticeable difference to their coat at all. But neutering stops that really strong stink of their urine, which is the norm for intact males. And also halts indoor marking in most males. But as others have noted, it won't stop a dog peeing on its feathers.
There are of course strong health and welfare reasons for neutering a dog that you might also want to think about, as coat texture is really a very minor issue in comparison to, say, having your dog stolen by the unscrupulous to be sold on to puppy farmers to be used for breeding, which happens on a frighteningly regular basis with this breed in many countries, including Ireland. It is very easy to see that a male is intact and such dogs are often stolen and sold on or kept for breeding by people who often do not keep the dogs in very humane conditions (I know -- I get what were obviously once pet dogs into rescue fron puppy farms on a regular basis and the places they come from are often hellholes, and the dogs very neglected). They also seem to be a breed of choice and regular target of some unscrupulous individuals in the traveller community for example and are quickly moved on and never found by very upset owners. In addition, an intact male is going to have an enormous drive to get out and roam –when I did regular dog rescue working with one of the Dublin pounds, about 70 to 80% of the dogs picked up by wardens were intact males found wandering, and sometimes roaming in packs attacking females in heat. And therefore they are also more often the victim of road accidents. For these and other welfare reasons, no reputable rescue for example would ever home intact dogs -- and many breeders around the world only home to pet homes on spay/neuter contracts.