Based on what I know, either MF or Kioti. MF is part of AGCO and gives you a full range of tractors with known quality and name recognition even for people in their 90's. The MF and AGCO tractors I've seen look good, and importantly are bought by farmers as well as homeowners. MF also has a number of implements besides just tractors, like hay balers, and that lineup could be valuable too. MF would be my #1 pick if all other factors were equal.
Kioti would be my other choice. Their product looks excellent, offering full features while undercutting big 3 prices for similar size and features. I think they are a bit handicapped by their small dealer network. Also, while I don't think Kioti will disappear any time, I can see that someone who is older and more cautious would feel better buying Deere/NH/Kubota/MF.
I have looked at Branson and Mahindra tractors at dealers and farm shows, and I'm not likely to buy either one. They look much more basic compared to the big 3, plus AGCO/MF and Kioti. I guess some of the Mahindra-badged tractors are now made in Japan Mitsubishis, but that doesn't change my view. I know that both should have "some" price advantage, but in my area it doesn't look like enough difference to justify the older tech, less refined construction, and reduced features.
Of course I don't know relative profitability, dealership requirements or financing arrangements for those brands, all of which would be quite important to me from a business perspective.