You can cut out a subfloor that fits over the stairwell with a seat mounted just the rear edge of the well, it gives a large area just in front of the seat. Put matching flooring on the cover. A countersunk lifting ring allows you to pick it up easily and it stows between the right seat and the wall.
Some I have seen have replaced the door for more security and weather seal. With the floor down, the double style door cant open even if they push heavy wire through the door gasket and activate the opener.
I've looked at them as well and still considering this type vehicle. MPG, depending on weight seems to be 10 to 12 going light and 8 to 10 heavy. The are not too aerodynamic. I have dibbs on one at an upscale retirement home where they take good care of their vehicles as limos.
My question is, do I (or you) really need a better departure angle?
I'm a tad concerned about the lowest step too, cutting that out and raising that at the bottom requires some body fabrication, not rock science, but work and money.
I saw another one with a but of the rear used as storage. The back door could be opened to store a genset, oil and lubes, cleaning stuff, etc. Higher up were cabinets that opened to the inside over the bed.
I'd put the bed in the rear, some storage, then the bath, head on one side and shower on the other, Then living area dinette and the kitchen forward mainly behind the driver. Planning is the fun part.
At the rear I'd like a outside ladder to a rack that doubles as a sitting platform with rails that fold up from the deck to an upright position. Don't forget the umbrella. A guest room could go up there too. Forward can be solar.
I've check on parts, A/C could hurt, 6 tires about 2K and brakes could be a grand. I have no idea how big of a winch would be needed. Lots of room for tankage under the body.
I think you got a hell of a deal, these can be had for 3 to 5K but not with 25K miles, that's just getting broken in! Subscribed! Post pics!