My 2 cents.... operating a 33hp Massy... 63" wide, 3200 lbs without the loader, R1 Ag style tires - operating on 200+ acres... very little level ground... almost all woods - slopes in excess of 18 degrees...
It all depends on what you are doing! If I am just moving the tractor across the slope, I always have
ballast on the rear and front - trying to keep the machine in balance.
We don't have spacers on our wheels. We don't have our wheels pushed out to max width. Why you scream? Our trails are narrow and we are working them to get them wider. Our implements are all 5 foot as a 33HP machine is not great at 72" implements. Still, being mindful of how we are operating, we manage.
Have I lifted a wheel? Sure. Did I keep going and did I push to see if I could "make it through?" No. Never. If a wheel looses purchase, its a drop and stop. Get out of that situation and think about a new way.
Regarding height... while I would like a larger machine for a lot of reasons - power being the biggest - I don't know how well I could work back in the thick woods with a taller machine. Its a challenge at times now. I have caught the ROPs on a tree limb that I ignored... a lesson learned. Keep your head about you.. but wear a hard hat in the woods! (When working trails, we keep a pole saw handy!)
Bottom line - while I appreciate all the guys who comment about working on hills, needing ballast, and all that, because they helped me when I was a super-newb. Now, as a 400 hour newb who has been doing all sorts of craziness, I have learned that my seat is my best indicator of whether or not what I am doing is right and safe... When I feel the machine leaning, when I sense that wheel about to rise, I know to stop and re-think what I am doing. Don't push and don't keep trying. Stop. Re-Think!
All that safety stuff helps when first learning but don't go nuts with it. I think you can tie yourself in knots with worry. I know I did.
I don't have a choice in the machines I get to operate and the way in which they are set up. Its not my purse doing the buying. I make suggestions and when I really feel I'm being asked to do something unsafe, I flat out refuse to do it. That's happened several times.
The result is that the property and machine owner will hear me when I refuse. We then talk about a safe way to do that which he wants me to do. Only when we have a safe means will I then attempt it and I will do it ever so slowly and carefully, building confidence in our decision as I go.
I only have one life to live. I get a lot done without all the stuff people here say I need. If I did not try with the little I have, I would get nothing done.
Your body will warn you. Listen to it. When you have something you need to do and you feel unsafe, then I suggest you consider, "What might I do to make this safer?"
I know there will be many here who will argue that I am a fool. Okay... but I have been tractoring now for 7 years - all of it on pretty tricky slopes. Have I made mistakes? You bet. Which were the near disastrous mistakes? The ones where I did not take the time to stop and think.
Your key is you. Do every job with the thought that "I only have this one life to live." If you do, I am sure you will do things in a safe manner no matter what tools you buy to help protect you.
If you have an unlimited budget and can afford everything that has been listed you should have, then by all means, buy it all. If like most of us, you have to manage a limited budget, buy a machine on which you can make changes as needed to suit the job at hand.
One final comment: I prefer a geared tractor for the hills. We have an HST sub-compact. I don't care for it on the hills - I can't explain it.. I just don't feel the assurance of the machine being held on the hill with a slush box doing the holding. I like the gears... If you can, I suggest you get the dealer to let you run an HST and a geared tractor on hills. See which gives you the least seat pucker. Or find some neighbors who will let you try their toys.
Our most recent toy is a tracked skid steer loader fitted with a brush hog. The plan is use it on the really steep slopes. I'm going to watch the property owner do that the first time! My seat is already puckering when I think about the 28 degree hill he wants us to mow! I keep hearing the song, "Slip Sliding Away... Slip Sliding Away...." hehe There is pond at the bottom of the hill. Could it be that our skid steer will be taking swimming lessons this summer?
Sorry for the long post...