The 'tree of life', perfection, and everlasting life stuff has always troubled me.
If the tree is symbolic, why place a 'flaming sword' to guard it? If the tree is real and has the properties implied by God, this seems to go against his own word. He stated that if man ate of the 'tree of knowledge', man would die. Well, since man ate and since God cannot lie, how could the 'tree of life' possibly do anything that would reverse His sentence of death? There should be no need of guarding the tree if God's word(sentence of death) cannot fail.
If the only reason man dies is because of sin, why do animals die? They seemed to be dying already in the garden since God uses animal skins to clothe the humans. Why don't angels that have sinned die? Longer life spans? They have to be killed in the end.
And what about the phrase '...has become like one of us in knowing good and bad...'? If God is the 'only one' who determines what is good and bad for all of his creations, why the word 'us'? Sounds like someone else is able to make their own decisions for themselves.
Additional thoughts: How do you 'deceive' a perfect person? Why weren't Eve's eyes opened until after Adam ate of the fruit? And, of course, we can get goofy and ask if an animal that happened to eat of the tree of life, would it live indefinitely?