Print debugging is fine and all but I find that it pays massive dividends to learn how to use a debugger and actually inspect the values in scope rather than guessing which are worth printing. It also is useless when you need to debug a currently running system and can't change the code.

And since you need to translate it anyway, there's not much benefit in my mind to using something like msgpack which is more compact and self describing, you just need a decoder to convert to json when you display it.