This is where Richard is sorely missed by us all. He was very thoughtful with information about boats for particular people and purpose.
I'm certainly not the one to advise: we live in the past and select our favorites among the best of pre-WWII naval architects and yards. So, none would appeal to David or I and we're not good reference at all.
But if you ask a cruiser to opine, well then, they'll opine
I have no knowledge of the rudder or underwater profiles of these boats..
Tha Amel 53 super maramu-- That would be a ketch and certainly having the split rig can make life a bit nicer. It's less of a worry to deal with smaller sails. It is center cockpit and with it quite forward from pics I've seen so--not exactly my own preference as I like aft cockpits from the perspective of a bit drier overall. The boat is slick and pretty though!
Davidson/Cavalier 49-- no opinion other than it's the least lovely of the three.
1990 Oyster 55 -- there's what maybe 50 of these total? It was a successful boat for sure. It does have in - mast furling and I don't like that but I think only the Davidson would have boom furling right?
I really believe you should consider letting go of the idea that you'd like a modern boat for shorthanded sailing with loads of room aboard. Consider getting into something like we have: Pre-WWII, wood and built in such a way that even though you've got 50-some feet on deck (and almost 70 overall) you've only got the room below of a 40ft modern boat. You'll feel right at home in those smaller quarters! Yet, you'll have the waterline for speed and stability in larger seas, too. You'll never have to worry about new-fangled equipment breaking or going out of style, you'll be able to fix and remake everything aboard, from scratch, wherever you may arrive.
OK, enough of that-- I wish you the best of luck and truly would love to know more about your decision process and why you're leaning one way or the other.
With used boats, its all about systems and I am unfortunately not familiar enough with what would have been standard/stock on any of the three vessels to speak with any authority. I do remain interested in what you're up to and really want to know how the selection is going!
Warm regards, Brenda
PS David says "hi!" and tells me to sell you a bit harder on the classic boat cruising concept.