I think the easiest solution is probably to make a platform that accepts the new one key module or something similarly low-pro like the kalih pg1316s switches. it’s probably possible to hijack the usb line the original keyboard is connected to with 1 pcb, and to mount the keyboard on one more. this reduces the versatility (no drawing tablet) and now requires some more technical expertise, but it allows custom keyboards without changing the 13 form factor. the hinge raise is probably the hardest part of your idea, but it’s definitely possible