This is the kind of question that is bound to result in a lot of discussion and strong disagreement. As I see it this is the kind of discussion where almost any opinion is bound to have truth in it and to one be degree or another be misleading as well. The reason that I say this is that the reality seems to be that almost any boat in the right highly skillfull hands, with a lot of luck, and with a bit of care can sail around the world. But very few production boats are ideal or even reasonably well suited for a circumnavigation, almost no matter what you do to the boat.
So, as soon as someone says, this model is ill-suited to a circumnavigation, there is bound to be someone else will give an example of a sistership that did one.
In my mind when you ask about the suitability of a boat to make a circumnavigation, it is about managing risks, having a boat that is adequately robust to not only withstand extremely harsh conditions but the wear and tear of a vast amount of time under sail. It is about carrying capacities and the ability to sail well in an extreme range of conditions. It is about an interior and deck layout that is comfortable and safe at sea, while being comfortable at anchor or dock in all kinds of weather. It is about the kinds of storage, ground tackle, and deck gear that lends itself to safely handle whatever you encounter. And that brings us back to your question.
Morgan Out Island 41's varied quite widely thoughout their production run in terms of fit out, and construction standards. In a general sense these boats were intended for the charter trade, and so were built cheaply, moderately robust for the short haul, were optimized for the wind range they were likely to be sailed in 10-20 knots and were equipped and rigged with gear that was anything but optimized for the wide range of conditions that one would expect offshore.
When you think of a circumnavigation as compared to a typical coastal cruiser or even a charter boat, they are exposed to enormous use. A heavily used coastal cruiser might sail 500 to a 1000 miles in a season. A charter boat that was used hard might sail 1500-2000 miles in a year. But a circumnavigation is well over 40,000 miles. In other words, you are talking about doing the equivillent of 40 years of coastal cruising on a boat that is already 25 years old. If nothing else that should give you pause.
But when you look at the specifics of your boat the equation gets a little worse. The Morgan 416's were constructed with minimal internal framing, pretty widely spaced bulkheads, and a turned out flange hull-to-deck joint adherred with 3M 5200 and widely spaced bolts (depending on the year and order option). At least on the one that I knew, the bulkheads were skip tabbed to the hull and were not attached to the over head. These boats are known for the way that the flex when they are in heavy going. With their comparatively heavy hulls on these boats, that may still be adequate for coastal use or even the 5 to 7 years of charter that these boats were designed for. Given the sheer amount of wear and tear of a circumnavigation, the flexing will take a toll on the strength of the boat, potentially weakening the hull and the H to D joint.
Then there is the hull form, and draft. These boats have a miserable motion in a blow; Real rollers with a sharpish snap at the end of the roll. Again, it is possible to circimnavigate no matter how poor the motion that the boat may have, but if you ask me if any boat is suitable for a circumnav, then I would want to know that its motion comfort is well above average. No one who has spent much time on these boats and has also spent time on other boats that actually do have a good motion would ever say these boats have an above average motion.
But beyond all of that, even if the boat was robust enough, and had adequate sail and anchor handling gear, and had a great motion, the interior layout is ill suited for prolonged offshore work.
So before someone jumps all over me for saying the Morgan OI 416 is ill suited as a circumnavigator, because sister ships have circumnavigated, I will admit that I have heard it said that people have taken them around the world and therefore at least in some one's mind (just not mine) this proves that they are suitable circumnavigators.