I've always thought that being cast out of Eden was not so much a punishment, as merely an unavoidable consequence: having eaten from the tree of knowledge, we now also have the ability to appreciate suffering, and thus no longer experience paradise. That would make paradise a state of mind, rather than a place.

After eating the fruit God lists a number of consequences, which sounds somewhat like a punishment, but that could just as easily be interpreted as "well, I didn't want this to happen to you, but now that you got to this point, you'll have to deal with the following". That includes increased pain in giving birth (a consequence of having larger brains), and the rise of agriculture. Eve is also only named after eating the fruit, not before.

The snake gets cursed for what it did, and so does the ground, but not Man. God even goes so far to provide them with clothes, and acknowledges their growth.