I am glad there is one of these threads active. I was thinking about this today and what if Itachi's gift to Naruto went something like this: Itachi wanted Sasuke to have his eyes, we know he gave him Amerterasu, abut he also probably knew Tobi's plan for his Sharingan and EMS. So, he wanted Sasuke to end up with his eyes in the hope that eventually Sasuke would defeat Tobi.
However, knowing that Sasuke was not evil in his heart at the time, he gave Naruto a gift, because if Sasuke ever hurt Naruto, it meant that even Sasuke was truly evil, and probably more powerful than Tobi with his EMS.
So, to stop Sasuke's evil power, by ending his EMS, and to protect Naruto, Itachi gave Naruto a seal or a curse or some trigger that, if Sasuke ever attacked and killed Naruto, the gift would trigger, and it would force Sasuke's (Itachi's) eyes to cast Izanagi on Naruto, both reviving Naruto and closing Sasuke's eyes.