(Sorry for the late reply, I thought I'd get an email notification of any responses and didn't see these until now.)
@WanderlustAV The platforms have worked out well -- I built two, each of them is a 55" x 24" piece of 1/2" plywood, with a 2"x2" that runs the full 55" length on each side of the plywood. When not in use I keep them stacked on top of each other right in front of the built-in platform, and secured with a ratchet strap just to make sure they don't fly around if we had an incident.
I'm now in the process of removing the running boards -- got the passenger side off, but I'm trying to decide what do with the driver side and the power inlet -- need to figure out where that will get rerouted. There is a LOT of plastic exterior molding on my 2012 compared to the later models (at least based on what I can see from googling images of the N6), and the molding that extends around the front wheel wells down to the running boards is in awful shape. I can see why they ditched it.
Thanks to you and @rvivian for the seat cover suggestions -- I'll check them out.