Are you using a 90 degree clamshell folder for your Mil-T-5038? I find when you cut it on the edge like you have on the shoulder straps instead of having one continuous binding run with rounded corners you get a lot of wear. Also it cuts down your machining time as its just bind, cut, sear instead of bind, cut, sear, bind, cut, cut, sear, sear. Your binding has jumped off on the back left where your drag handle mates up to the rear.
I really like your back panel, the form really flows but I would have sewn the 2" webbing down in a box/cross with tacks on the end, maybe another row of PALS on the base to increase real estate a bit. The bib being squared off at the edges takes away from the nice form of the back panel in my view as it goes from nice curves that wont snag or rub on clothing to a box.
A feature I recently started incorporating into velcro closures like you have on the main compartment is to have a 1 1/2" gap in the centre of hook/loop as opposed to the webbing tabs. I got the idea off a Crye Gen2 shirts bicep pockets. Its less on your cutting sheet, a wee bit less weight and one less thing for machinists to do. You might have guessed but I do something similar to you for a job. I don't know how it is for you but labour is our biggest cost to make anything so anything I can chop out of the build process without compromising strength or function is a good thing and helps keep the cost down. Being a former Grunt I still feel bad charging guys a lot for stuff.
The helmet cover is really nice. I've been dying to play with one but noone has ordered one as a custom job and we don't have cool helmets down here to build them for, just generic TC-2000 types.