Mornin' Mikey,
Congrats on the move. I think you'll find the country beats city living by a mile.
I'm voting with the 50HP guys. Sounds like your plans are still a bit hazy and 'someday' may be years off. Something that gives you flexibility and does the work you need done now, without costing a ton to own or operate may be your best bet. A simple, straightforward 50HP utility tractor with a few good options should do it.
A 50HP utility will normally have a Cat I/II 3 point hitch. This will allow you to use either the smaller and lower cost Cat I implements or the heavier duty Cat II. That way, if you find a good deal on either type, you'll have something that (within reason) can handle it. 50HP isn't so strong that it'll trash well made Cat I implements while it is strong enough to handle the smaller Cat II implements you might find useful on 50 acres.
The 50HP ute would let you maintain your property and give you a foot in the door if you go to haying...certainly with small square bales it will. If big round bales turn out to be your choice, a large, used 2WD Ag tractor purchased when these plans firm up would make sense. If you go the biggest you might ever, ever need to begin with; you'll be stuck with a huge inflexible beast that will often just add to your problems.
As for options, a front loader will prove to be incredibly useful. Even if just used for lifting things and moving them around, you'll wonder how you'd ever get along without it. 4WD will make the loader much more effective for true loader work plus give you the ability to get out of trouble (e.g. getting unstuck) when working alone...within reason, of course.
A year or two down the road as your plans firm up, you'll probably identify many ways a 2nd tractor could help you. It may be the big 90HP beast mentioned earlier or, more likely, a 2WD Ag tractor of 30 to 50HP. Changing implements/hooking up & unhooking can waste a lot of time if you have a bunch of small jobs to do. The second tractor can save you a lot of time, aggravation and (if you're getting older) opportunities for mistakes. It would be good if the 2nd tractor could handle the same implements as the 1st.
With the same acreage as you, I've found the Kubota MX5000/5100 to be about the right size and price. Another good choice, if buying new, would be the JD5103/5203. New Holland & Case/IH make good tractors in this size and Mahindras can be a real bargain. Used tractors can be a bit of a crapshoot but, if you know the maintenance/usage history, can also be a good way to save $. As with anything, it's possible to spend more and get really deluxe versions; but setting aside the extra money for implements or a possible 2nd tractor may make more sense in today's economy.
FWIW
Bob