I think the Legendary Senin skipped the whole rank thing too, they were in the previous war and it never said that they had to take any exams (far as I know).
Would make a funny filler but.. eh we can do without. You can just look at the rank more or less as a position than a rank for them. If Kakashi gets hokage then technically Naruto would prolly be defaulted to a journin, even though he is the hero if the... well ninja world.
I could see kish doing something silly like making them go through the steps in the end, reminds me of every bad rpg I've played.. "You saved the [princess/castle/town/village/country/world/time era/multiverse/time...ect] Here is 5o gold and a healing potion, and remember if you need anything, go ahead and visit the stores and purchase everything at full price, discounts are for real heros..."
Would make a funny filler but.. eh we can do without. You can just look at the rank more or less as a position than a rank for them. If Kakashi gets hokage then technically Naruto would prolly be defaulted to a journin, even though he is the hero if the... well ninja world.
I could see kish doing something silly like making them go through the steps in the end, reminds me of every bad rpg I've played.. "You saved the [princess/castle/town/village/country/world/time era/multiverse/time...ect] Here is 5o gold and a healing potion, and remember if you need anything, go ahead and visit the stores and purchase everything at full price, discounts are for real heros..."