I did not want to get too involved. I wanted the open space to haul my works of art which oftentimes are crated in large, 80" long x 12" x 24" cardboard crates, each weighing about 45 lbs.. I could stack six of them in the back! I have already moved several around and noticed that these objects can encounter the walls where the wood panels are. There seemed little point in doing anything to the panels that would not withstand some abuse in my workaday world. This is why I went to the van from 15 years of mid-size pickups. I do have to make an effort not to inhibit that large, spacious back end. That cavernous interior is where it's value lies.
It's also my personal vehicle though, and that unfinished interior is not exactly attractive. My overexposed iPhone flash photo taken in the dark makes it look terrible, but in daylight if I look at it, it is just a textured black and seems to fit right in with the plastic trim. It feels comfortably finished now. Next I will be covering the barren rear upper side walls, probably with Alupanel.
The two remaining important issues I would like to deal with are the lack of rear ventilation, and that uninsulated metal roof (a simple local headliner job would cost about $500). I also need to decide upon what to do about some form of restraint that will allow carrying of things like grocery bags and odds and ends without attaching to the interior. I do have items in athletic-style tool bags that can be tossed around or removed as necessary when hauling space is needed, but I want to consider those solutions further. I also have some security concerns. The two extra 2nd row windows, along with the two in back, don't hide anything. I considered aftermarket tinting for privacy, but it's not an option I fancy much.