1) If kishi intended for Naruto to "END UP"... Now you yourself say "End Up". Now End up implies that he does not Start off with something but rather gets it later on... Now if he started off with half the chakra and minato gives him the rest then would that mean he ended up with all of it? And thus the splitting of the Chakra is essential to Naruto ending up with all of it. I really dont see how your arguement works, perhaps elaboration is needed?
2) Hmmm... Giving your son a gift that will essentially make him Twice as strong as he previously was isnt a good gift is it? I mean ya in a ninja world where power is everything I can see how making someone twice as strong wouldn't be considered a gift.
3) The best point you have made was that one could find that the other half of the kyubi wouldn't be much of a fatherly gift to a son... but then when you start judging things from that perspective you have to weigh how fatherly any gift would be and then any gift you chose would die the death of 1000 qualifications. But you do make a good point!! The kyubi chakra may not be the best fatherly gift a father could give a son.
How would the rest of the 9 tails make him stronger.
Chakra is just energy used to accomplish something. Naruto with what he has is pretty close to unlimited, the rest of the 9 tails would just be redundant.
What is he going to do have two times unlimited chakra, it wouldn't make him stronger he can't run out of chakra while in BM anyway.