You've got a good plan and glad to hear it.
My plan will get more sophisticated as the need arises I guess but realistically it will do what it needs to as it is. It's also a good way to double up my seed-back up in the advent of losing my Trezor (and my seed phrase). T-dog (no one calls him that) will have his copy for me. I reckon it's a reasonable plan. Maybe not as cutting-edge as some...But it'll work.