Wifey B: Good luck in your boat search. Plenty of boats to fit your needs, subject to price of course.
Let's talk size a moment. Yes, size is important.
I don't know how much time the two of you have spent on larger boats but, if not a lot, then I might suggest doing a couple of charters since plenty available in SW FL.
Here's the deal and I'm consulting hubby so I get this right, but he'd tell you a 50' isn't just 25% bigger than a 40' but more like 50% and a 60' isn't like 50% bigger than a 40' but more like twice the size.
Right now you're talking 50-60 and there are going to be lots here who would tell you both are bigger than you need. Listen only partially to them. Now, I'll tell you 60 vs 50 vs 42 is a huge difference. I'd always pick the bigger one but gonna tell you many and perhaps even most wouldn't.
The pluses of size: (I'm being very careful in writing this)
-Space, luxury, closer to the home you're leaving. It impacts every space on the boat from ER to head.
-Consider how many guests you will have. We have lots, but many cruisers find they have far fewer than expected. Kids? Grandkids? Nieces and Nephews?
-Storage. You're going to be parting with many things but size allows you to keep more. Things like clothes for all seasons. Cruisers take a few casual outfits and wear them over and over. If you're living on it, you'll want more.
-Sea Conditions. Assuming equal design, bigger handles seas better. That means more comfort and fewer days stuck by weather, easier to cruise outside and not be confined to ICW.
-Ability to have more convenience and luxury items from watermaker to hot water capacity to more fuel to freezer capacity.
The negatives of size:
-Expense. Larger slip. More costly to wash or bottom clean or paint. Lot's of things go by the foot.
-May be more difficult for one or two to handle. I don't buy this as much as some here. Handling isn't by strength or force. If you know how to operate a boat then handling bigger is as easy as smaller. At a certain size you need more people for some things but 60' isn't it.
-Needs more space in anchorages and might not fit in moorings.
-Keep an eye on draft, but also on air draft. Some areas can be challenges as either increases.
-May have more equipment, be more complex, more to break.
I'm for size, but you'll have to see what is right for you by walking them, trying them, etc.