OMG CommanderKitler! You totally popped my bubble. I knew there were some fragility issues inside due to poor assembly, but overall I thought it was a solid build. I am now scared to even speak loudly near my GPD now buah!
The XD is actually pretty solid it's just that the guts have lots of ribbon cables running through it so it has to be taken apart carefully.
I had mine apart just for shits and giggles and what the guy broke saying it was a "battery" was actually the microphone. It's in an awkward place and soldered on oddly so that just needs to be kept in mind. It's really not as bad as it seems.
It should be possible but You'd need some knowledge about circuitry, experience with soldering and some calm hands.
You actually don't need much experience to "hack" the antenna. There is a standard uFL connector on the WiFi chip so you could go on Aliexpress or eBay and look for "uFL antenna" and get tons of different antennas that you could just swap out without much difficulty.
You can even go as far as getting an uFL to RP.SMA Connector / 5dBi Antenna
. You could drill a hole in the back somewhere around one of the ports and have a massive external antenna.
I think the XD generally has a bad WiFi problem because of the bad soldering on the antenna itself. One contact should be soldered to the shield of the cable, while the other contact should be soldered to the internal wire.
I had a problem on my Q9 where they had used way to much solder so the connections had bridged and the reception was abysmal. It was an easy enough fix and I went back and fixed a couple old tablets I had with the same antenna and the same problem.