My five acres is 25% level, 50% moderately hilly, and 25% STEEP. It also has hundreds of oak trees. About as different from your terrain as can be, but I researched here last year before buying a new tractor to replace the old one I'd bought off Craigslist.
I started by researching brands and models, and soon realized that most vendors had one or more models that would work for me. Many brands share manufacturers, with paint color and minor feature differences. Some vendors use multiple suppliers, with one model being made in Japan while the next is from India. Every brand has satisfied customers, and every brand has it's detractors. I think most of the tractors sold in the US are reasonable quality.
For me, it came down to dealer and price. The Deere dealer here is huge, with a lot full of inventory in every model. They are so big that they have a salesman just for Compact Tractors. My guess is he just failed out of junior college because he didn't understand any of the questions, and thought the answer to every problem was whatever product the boss had a bonus on. He was actually worse than no help at all.
The Mahindra "dealer" was a trailer dealer. No service department, no parts, but he could get you financed...
The Case dealer was an exceptionally nice and friendly fellow, who spoke highly of the Kioti dealer and the Kioti brand. His product was severely overpriced, though.
The LS dealer was much like the Mahindra dealer.
All this left me looking at Kubota and Kioti. Both are long-time tractor dealers here, nearly a century each. Both have full dealerships, and the Kioti dealer has two locations. Either would be satisfactory, as they were both pros in the business. The Kubota was a little more refined, but the Kioti was more capable - both in capacity and weight. (Then again, Mahindra beat them both on paper - the dealer was the issue there.) The Kioti was also less money - a lot less.
The Kioti dealer really went the extra mile - even offered to deliver the machine I was considering to my property (40 miles away) and let me demo it for the weekend, no charge or obligation! He ended up doing a dealer trade to get me exactly what I wanted, and made me a great deal on it. After I'd run it a while, I found a couple of minor issues - and he had a service tech up the next day to address those issues. He went over the tractor and checked all the loader bolts and such while he was there, as well as the stuff I'd called about. Left me a detailed note - no charge.
Bigger and heavier truly is better when it comes to tractors. I bought the biggest that I could fit through the trees at my place. The next model was 18" wider, and just would not have worked as well.
Take a look at flail mowers if you get a chance.