I saw "ASN.1" in the draft and immediately thought "over-engineered".
When bytes count (and they often don't, but in this case they probably do), what would be your preferred system? And what do you see as your favoured approach's main advantage(s) over ASN.1/BER?
ASN.1/BER is a pain in the ass. I'd rather gzip json. Or poke chopsticks in my eyes.