......................... very few women over 50 who'd happily bathe on deck ............. That extra 8' to 10' of boat length can make a huge difference to the livability of a boat for a woman and the length of time she will remain aboard.
And it's nice for the men too, not only to have the 'significant other' aboard on passages but to have the creature comforts of home for our own use
Also women are more prone to mal de mare than men are, and a bigger boat has a much easier motion. My wife doesn't get sick in gales any more on our larger boat. I have known many couples give up the distance cruising dream because she finds the motion too miserable to tolerate.
To try and put figures to this, generally for similar styles of boats in the same conditions and looking at roll pitch and yaw accelerations a 60 footer will be 5 times more tolerable than a 40 footer or 1/5 the motion. Even a factor of 2 is significant. That easier motion also makes the deck a much safer place to be in rough weather.
Passages can become not only tolerable but can even be fun rather than just the miserable existence out there between ports of call.
A bigger boat is actually easier to handle in most docking situations; things happen slower and you have more time to make decisions. If you can handle a 30 footer under any conditions, you'll be able to handle a much heavier 50 footer without any problems, once you get used to the extra few feet of boat. Don't sell yourself short; if you can handle one boat, you can handle any boat, once you get used to the peculiarities of that boat.
Agree, boat handling is easier, not harder. When coming alongside a dock or picking up a mooring, the bigger boat stays on station much longer and gives you a lot more time to pick up/make fast the line(s).
If you read the older sailing books late 1800's through to the 1950's people often circumnavigated short handed in very heavy displacement sailboats well over 50 feet without problems. These days we have the huge benefits of all the technology they didn't have. We can use the same seamanship techniques that they necessarily had to use, unfortunately a lot of boaters today are unaware of many of the techniques that make big boat handling easier.
An example mentioned before would be maneuvering using a midships spring line, many smaller boat sailors don't even have anywhere they could attach one and don't understand how it's used, so they miss out on understanding how a much larger craft could be controlled with one line when arriving or departing shoreside.