Your primary concern is your back, and that cannot be fixed by a particular car brand or type of seat. It is a for manufacturer a huge challenge to build seats that fits all. In some cases, the most basic cars can deliver more seat comfort than some advanced multi adjustment seats in high end cars. For example, my wife who is 5ft, and weighs about 45kg sits very comfortable in her 2017 Lexus RX350. I am 6.3ft, way to heavy, and cannot find a good seating position/comfort in this SUV and will not last a ride to Abu Dhabi. But I feel very comfortable in the much bigger seats of my 2018 Silverado; I can drive a whole day without complaints.
I see here a lot of support here for Pajero's; they are great SUV's, but they are of an old design and do not set high standards on overall comfort. However, depending on your posture it could be that your back may feel very comfortable in that seat. You just have to try it during a long test drive.
I am also quite sensitive to a good seating position and quality, and found 3 brands that did very well for me in providing me seating comfort. Volvo (the best), Chevy and Mercedes. The worst in my experience are Ford Explorer, to short and narrow and Toyota Landcruiser, to short and bad backrest). Many people may disagree, and that is correct... its personal.
Test drive a lot of different cars and take your pick....