May be a bit of a noob idea, but I purchased a roll of 1050 denier ballistic nylon fabric (the stuff they make luggage out of) and have wrapped all of my dock lines in it. I made simple sleeves on a sewing machine and pulled the line through it. The sleeves take all the wear, protecting the lines. Cost was less than $50 for the roll. Two yards did all 4 of my dock lines with a ton left over.
https://www.onlinefabricstore.net/bl...on-fabric-.htm
Couldn't you do the same thing for the mooring ball line(s)?