The one thing that I might have to offer that is different from the many wonderful posts I've read is to look at the word "as". "on earth as it is in heaven" Could that mean "in the same manner"? Are we to respond to God's will and do His will with the same attitude and completeness that the angels do? Joyfully, happily, without reservation, totally, completely, all the way, nothing held back. In total awe of the majesty of God. With total reverence. With all that is in within us.
This is a new way of looking at if for me and one I will be trying to make part of the fabric of my being.