What I mean is this, something that makes about half what what you make at sea but its still good money and you are still at home and you can pick it up or leave it when its time to come or go. I. E. open a store and have people manage it when you are gone, drive a dinner cruise boat a few timea a week, start a landscaping business, day trade (I suppose you can do that when you are at sea too), sell stuff on ebay, be a part time surveryer for houses - or for boats, real estate etc.
You can do anyone of those. I sometimes steer a dinner boat also. If you can start a business and have someone run it well when your at sea go for it. Thats just extra $ for you and your retirement. Or early retirement.