As easy as a BH77 is to remove behind the LX, I can't imagine WHY anyone would mow with it on. A backhoe has one purpose. To sit still and dig. Ok, well, if it has a thumb, a few more. It ain't for off-roading or moving fast to do anything. Going fast with a backhoe on a tractor is a good way to break the backhoe, or the tractor, or worse yet, YOU.
To a point, I agree with the sentiments of getting a separate yard machine for mowing, if all you have to mow is grass, and only a couple acres of that. Obviously, if you have more, you can get a bigger mower. If you want something to dig with AND cut grass, the LX2610 or LX3310, particularly the SU (Special Utility) model is the cat's pajamas for dollar spent. If you want creature comforts (cab, cushy seat, cruise control, etc), then the SU is not for you. The SU, however, comes standard with larger wheels/tires, which do everything to mitigate the dangers of hill work, but is it enough? NO. NO. NO. That requires experience, and a generous application of safety.
The SU model targets the market of folks that want backhoe capability without a second seat and don't need luxury. The BH77 comes in two flavors, one for the SU, and one for the other models. The one for the SU does not have a second seat pedestal. The SU is better suited for a backhoe because of the higher ground clearance (larger tires/wheels) which also improves departure angle (angle where the backhoe will drag going on or off a trailer or steep grade change).
The CAB models targets the creature comforts market for folks that are going to spend long hours on the machine. With a cab, however, the backhoe obviously has to have an extension for the seat mount, which makes the angle of departure even worse, and is further aggravated by the smaller tires (lower clearance). The large tires cannot be installed on the non-SU models unless you want to pay for a mid-PTO output that you cannot use because the tires will interfere with anything under the tractor. MMM's are the primary reason oversize tires are not recommended for the non-SU models.
If you're in an open field with plenty turning room, I would recommend a 3PH mounted mower. I'm currently shopping for a mower that's going to be able to handle some rough stuff, but will also be useful as what I cut becomes more grass than rough stuff. If it's pasture, i.e. something that doesn't need a 'golf-course finish' but you want to keep fairly short, I'd use a flail mower. If you're just keeping high weeds and underbrush at bay, a rotary cutter (bush-hog) is fine. If you're looking at a golf green finish, better get something that doesn't tote around a backhoe. I can't think of anything more contradictory than a backhoe rig with turf tires. Sorta like having a screen door on a submarine.
Hills and tractors with a high COG do not mix. It's OK to go up and down them, especially if the heavy equipment is on the 3PH fully lowered. But NEVER go across them. The OM will explain most of that to you and what the limits are. If you feel puckery doing it, you probably shouldn't be doing it. If you're not puckery doing something the first time, you should be.
I'll reiterate my favorite analogy. Tractors are dangerous. That's what makes them useful. Recognize the tractor's limits as well as your own, or, you become a statistic none of us likes to read about.