I had this problem when moving aboard. Among other things, I needed personal liability because of earnings power. Remember that regardless of what you actually make, in some states a jury can award
damages based on the greater of your actual earnings or your earnings power, which some smart plaintiffs attorney will get an expert to testify to.
This is no joke, buddy of mine from law school
went to work as a public defender after graduation. Two years later his dog bit someone, a scumbag of a plaintiff's attorney took it all the way to trial. They brought in an expert explaining how the average salary of his classmates was $130k a year (UVa law school), they pegged him with $200k in damages and garnished his wages as though he was making $130k.
If one of your assets is your degrees / intellect / talent... You need liability insurance
I sent you a PM with details about the folks I use. When I looked into this, there were really only 1-2 real options for liveaboards, unless you were looking into a custom policy (e.g., your assets exceed $10M)