Owning a boat is not about a balance sheet of economic satisfaction. Owning a boat is about doing your own thing. If it were about economics, just go to the store buy your fish. There is something about making your own weights, tying your own mooching rigs, running your own boat, learning how to catch the various species of fish that holds it's own rewards. When you run your own boat you are the one responsible for the out comes. When you go with a guide, he is the one who is responsible for a successful trip. I have nothing against guides and if one just fishes once in a while it may be a good way to go. But if you are a hard core fishing addict and enjoy the intrinsic value a of do it your self life style, then by all means buy a boat.
As for the 16' Hewescraft in the ocean I'll be honestly blunt in my opinion. No way. Two reasons one the open bow and two the stern well. Sure on a calm flat day one might be able to get by, but one can not guarantee the ocean will stay flat. Then there is the problem of crossing a bar to get into the ocean and also the return. Just my opinion but an open bow boat on a ocean bar can place one in jeopardy if a wave should happen to fill that bow. The water forces the bow down and the stern up. With the stern up one losses not only propulsion, but also steerage. This creates a situation for disaster. The stern well is a problem for a following sea or a wave coming in on the stern. This is the reason most newer ocean boat have the offshore bracket.
I know of three capsizings that have occurred with open bow boat on ocean bars in Oregon. Two of those capsizings were operated by professional fishing guides. One cost a mans life. The third was a member of this forum and he along with his two passengers lost their lives on the bar at Bandon.
One can roll the dice and come up a winner, but it does not always work out that way. I fish the ocean, but only with an offshore boat. That boat has a six man life raft, radar, AIS system, epirb, three vhf radios, and all the safety gear.
This was a good question "but how about near shore ocean fishing?" The most dangerous part of ocean fishing is crossing the bar, no matter the size of your craft.