I agree with you , pretty good observation !!
There is a debate in NB about Naruto has Kyuubi chakra anymore or not !! I would say that's not important because for your theory even if Madara drained all of Kyuubi's chakra out of Naruto , Minato still has half of it and can deliver it to Naruto !
So in the end , Naruto CAN have all 9 tailed beast chakra !
i like this