It sounds like you are well aware of proper tongue weight but just in case to emphasize as Dingbat suggests > here is a short vid regarding the dangers of improper tongue weight
link.
Given your current situation you could even do a little experimenting by adjusting it at either end of the 10 to 15% range and take it for a test drive to see what you are most comfortable with. To get your overall trailer / boat weight, in order to dial in the proper tongue weight, I have also found both the local rock quarries as well as the tractor scales on the freeways very accommodating in measuring up trailer (and combination weights). I just go talk to them first and explain what I am looking to do. I even once measured passenger to driver side on a 33’ travel trailer to ensure I was loading it properly (left to right) for a long haul I was prepping for.