I don't know if it is presumptuous, but I do like your emphasis on the plain meaning of daily bread because it is so plain and ordinary. It is too easy to take the plain and ordinary for granted and fail to see how magnificent the common and ordinary things are.
But I don't think anyone has taken note of what I consider to be the most important word in "Give us today our daily bread." It is the word "give." To give means to render a gift to someone, and a true gift is not wages for a job well done. To receive our daily bread, and all the other things that support our physical existence, is a gift indeed. We say grace before a meal to give thanks before participating in God's bounty. That is certainly a state of grace.
Eucharist means thanksgiving, and that is the important idea. We never enjoy the world aright until we gives thanks for every common and ordinary thing--no matter how small and seemingly unimportant--as gift. When living becomes thanksgiving, I think we come closer to what Geothe was referring to when he wrote: "So waiting, I have won from You the end, God's presence in each element."
That is an excellent point. I guess we've been so focus on our "daily" needs that we forgot the "giving" part. Isn't that always the case.
This is the thing, really; whether the "bread" was meant solely in the gastronomical sense or also in the spiritual sense, the overall meaning is eucharistic: it is a petition for gifts not earned.