It's still unclear what you're trying to protect yourself from? What's the attack vector? What's the attack surface on your system?

It all seems like, "We can generate a unique key for each computer and that's enough."
But damn, that's not enough at all.

Always better than a clear key in /boot or nothing

It protects through obfuscation. Putting the key on a USB stick has no real benefit, first for reliability reasons, but also because deriving it from the hardware means each PC gets a different encryption key, and to understand the obfuscation you'd still have to decompile the binary.

It's completely unclear what this project protects against. If the computer is completely stolen, then all its unique identifiers will also end up in the hands of the thief. If anything, only the hard drive is stolen. So, a very simple solution is to store the disk encryption keys on a flash drive connected not directly to the motherboard, but through a simple extension cable. The flash drive itself is hidden in a tangle of USB cables.

What are you trying to protect and from whom?