I have a '78 3600 diesel with a loader on it. I have had it for a few years and use it around the yard for mainly light duty work. Not much heavy dirt work,etc. I have 60 acres of woods from which I cut firewood and use for hunting. The loader is used there to carry firewood out and to haul around saws, cant hook, tools, splitter, etc. Really handy for this, but again this is pretty light use. As my trails are narrow in spots, I have hit a tree or 2 (or 3) without damage so far. Low speed when this happens luckily. Really I just pretend to be productive, but it is great for getting fresh air and some exercise. Also do some snow removal, but most of this is done with a pickup and plow, not the FEL.
I mow several acres with a 3 pt. brush mower and have found the ag tires will dig in to the grass/soil when I turn and have the bucket on. So I take the bucket off to lighten the front end when mowing and that helps a lot. Could get turf tires in the front, but haven't gotten around to it just yet. Make sure your FEL bucket is easy to take off and put on.
My tractor/FEL were used very little for a few years before I bought them. Numerous seals leaked and required replacing. One coupler leaked consistently in spite of new "O" rings, but a new coupler solved that. It sounds like you are considering a new FEL, so this should not be an issue in that case.
Initially the back end was light, so I added fluid to the tires. Also often use an attachment like a back blade when hauling firewood. These help some, but often not enough. Down South's suggestion of rear end counter weight is good. Take that advice.
Mine also has power steering. Big help. Without PS you will work harder to do what you want.
I've been very happy with a FEL on my 3600, but I am not very hard on it. I often use the FEL when a wheelbarrow would do, and when the loader is needed, I don't use it for heavy work. One thing you will find is that working on the engine, etc. is not as convenient with a loader. More things in your way and they always seem to be right where you want to work.
All in all I'm very happy I have a FEL on my 3600. I use it all the time in ways I hadn't thought of before I had it. See pictures.

