For anyone interested, this conversation has been progressed on another thread.
Thanks for your insights on this @jasonzhu, it’s been really helpful. It looks like this wouldn’t be the low hanging fruit that I initially expected. Do you know who the best point of contact for this would be in DFINITY? It seems like it would be a useful feature in general to allow a canister to be rebooted without needing to specify any new WASM at all.