Ya the diesel mules are significantly louder than the gas. I went dead set on buying a diesel because of bulk tanks and its easier to transport. After riding in both the gas was too quiet to pass up. We nv, thermal, and run dogs out of the gas one. They are one of the quietest on the market. The diesels for all the brands are louder though.
The complaint about the seats are pretty common for most people you height. That why 6'3 guys like me feel so comfortable in them.
I test drove most of the new brands a couple months ago when we bought the new PRO. I had pretty much a blank check to get ever I wanted for the ranch.
The Polaris 1000 is very peppy but has 3 drive modes and a bunch of other non-sense. For the size the cab did not feel roomy. They turn like a bus and cost like $20K.
The Can Am 6 seater is nice IMO. It would probably be my #2. Its another $20K unit.
I have always liked the JD seats and layout but the 6 seaters are huge. I would take the single bench in a heart beat.
Kabota has some IRS units now with the CVT. That would be on option also. Kubota is a good brand all around IMO and there is one on every corner. I would not own one of the hydrostatic ones.
I ended up buying the ranch a PRO like mine and we put one in the budget for next year. The size and dependability is hard to beat. I can whip the PRO, with the two bench seats, all around in the cattle pens, thru the barn, and in the brush. I would not be able to do that with the 6 seaters from the other brands.
Different people have different needs. There is getting to be less and less difference between most of them like tractors and every thing else.