In my experience only, any one machine for all you ask of it is going to be a "compromise tractor". No tractor will do it all well, so prioritize. If you have the typical yard and house, ie. not a shrub, tree free yard with a square or rectangular house footprint. Unless you Roundup the heck out of your yard, with a 3,4 or 5 Series you are going to have places it simply won't go. We don't have anything in our yard and thanks to several thousand dollars spent on Pavestones our house no longer has nooks and crannies to mow; much easier to mow. We were lucky enough to start with a blank slate and designed our property with ease of maintenance in mind; could be done with 3 or 4 Series, but still not ideal.
You will just have to prioritize uses and get the one best suited for those tasks then get by with the others.
I can certainly identify with your situation, we have about ten tractors, but I can now only operate those with cabs. Our kids and grand kids now mow our yards with a BX2660, but if absolutely necessary I could do it with my 5740, but sure hope it never comes to that.
One of our neighbors has a 3520 with MMM and still needs a zero turn, another has a Kubota L3540 with MMM and still had to buy a zero turn.
Suggestion: Get every comfort feature available in your cab tractor, as you age you will be glad you did. Consider any short term or one time jobs and consider renting the right equipment, it's saved us a lot of money and fuel and allowed us to get by quite well with what we have.
I know I've not helped a lot on specifics, but that's because I can see no one tractor solution.