Damn.. that's some nice work. Doesn't look like you need to much help there!
You're a little late to say the least if you're just now trying to tackle the full planning of an updated LED suit and especially if you're trying to enlist the help of others in the final 4 weeks before the burn. You're going to have to use your head and think through this as best you can. It's good for you
For my LED suit this year, I ended up designing my own custom PCBs and used nylon nuts and bolts to secure them to the clothes along with 1/16" white laser cut panels to sandwich over them to diffuse and protect. My design is much more geometric than yours though and I'm going for sheer lumens with 2,440 total LEDs sequenced on 8 channels.
All I can say is to overbuild everything, as you know. Solder everything well and secure all those joints with heat shrink and other reinforcements. Use anything you can think of. Hell.. it hit me like a ton of bricks how useful duct tape is to give an extra level of support on the backs of those PCBs for the attaching wires. Spray adhesive + strips of naugahyde work great to secure runs of wires on the insides of the garments. The list goes on and many times you'll be coming up with solutions on the fly as new design obstacles arise. Just.. use your head.
Again.. this is good for you. You can do it. Get to it!