Yeah it looks great. I have been stalking you here and also ADV lol.
Can you tell me where you sourced the aluminum and clips? I plan to panel mine in the same way that you did but I have got windows in mine. I may use speaker fabric or something fairly durable on the panels. What's the plan for the bed?
The L-Track or aviation track I purchased in Canada from Kinedyne but if you are in the United States you have a lot more options like Cargo Control etc. I did even have to buy and ship some specific L track fasteners from the States as they weren't available up here.
I used 9 X 100 inch sections of L track so far and I have 2 other tapered L track 100 inch lengths for the floor area if I end up using them.
I used an indoor outdoor carpet for the panels as it's very durable.
You will be in for a very time consuming process making the panels around the Windows the same way I did but in the end any additional room created (for the windowless cargo) was well worth it.
Good luck with the build ask any questions I may be able to help with and post up some pictures when you are building it, I'd love to see them.
Edit - The bed frame I'm going to get a few other things done like finishing the window inlays before I really make a decision on. I have some ideas and have seen some great ideas but have been out of town working for the last week so nothing van related was accomplished.