The build is looking good. Man your getting close, I know it seems like you have a lot left to do, but your getting close. Make sure, as I am sure have already thought about, make the tail end of the decked area your wood / charcoal storage area. It is really nice to have all my wood and fire building supplies (
charcoal chimney, fire poker, charcoal, wood splits, etc.) right there.
My wood box is 18" tall x 22" wide x 48" long. Plenty of room for a 16-24 hour cook. Plus you have got quite a bit of room up on the V section of your trailer for propane tanks, burners, sinks and just about anything else you can think of. One of my latest additions has worked really well, the tongue box. I keep all my extension cords, a small tool box with a few tools that might and have come in handy, spare parts for my sink and water tanks, grill brushes, tie downs, my 12 volt power supply, lights, tarps, you name it, it's shoved in there.
$100 at Tractor Supply. Deep, wide and weatherproof. One of my last additions to my rig was also additional countertop space, I am much happier now cooking than I was before. I added some space next to the cook chamber so I can pull meat out and throw it on a cutting board right there, works great. Countertop space at a comp is critical. Quite a few cook teams will bring 2 to 3 tables, I bring one, 30" x 60" table, although even with my additional space I could use 1 more small table. I have considered making a lid /countertop for my wood storage area. This would give me way more space on my sink side of the setup, especially when prepping meat, plus give some weather protection for my wood and charcoal on the wasy to comps or just while it's sitting in the yard.
Hope some of this will spark some ideas for you and keep up the great build.