Klipper doesn't really offer anything in this case; in old printer cases it's typically used when I want to outsource the processing onto a Raspberry Pi or something, but we're not short of processing power here.
Also fighting to get all this machine's features to work with other firmwares would probably be doable, but a huge pain with very few actual gains.
Note that this isn't just a 3D printer, but a CNC router and laser too, thus the heavily built design.