1. Naruto will combine his sage mode with his bijou mode.
As already explained to master sage mode one requires massive amount of chakra . Naruto has become very good in the use of sage mode . To prove this fact in chapter where he escapes from the turtle island he enters his sage mode in matter of seconds while he is taking with iruka , also while battling with third rikAge he enters his sage mode just while taking with bee and eight tails , when rikage is destroying the rubber ball , and all rikage are known for their speed , so this proves a point he can enter the sage mode quickly and has good control over it.
Kishi has already shown this mode is possible on small scale when naruto fought pain when naruto was in this mode for short period of time ,after minato again redid the seal naruto suppresed the nine tails . Now this was on small scale as the naruto had only little charaka from kyubi. Then the question why is naruto not using it now then it's simple bcoz he is naruto to slow to realise it.
For sage mode one has to balance his one chakara with that of the nature energy or the nature energy will take over u and start converting you into frog stone, that is the point since naruto already has a large amount of the chakara given by kyubi he can absorb large amount of nature energy without worring too much about nature energy taking over his energy and converting into frog just has to balance it.
Advantages of this mode: 1. Madara won't be able to use his wood justu on him any more as if the wood tries to absorb kyubi chakras then nature energy flow into it Turing it to stone as it occurred with the pain. 2. Naruto taijustu and ninjutsu all will increase in strength by great amount taking them beyond only kyubi mode could achieve. That means stronger bijuu bomb . 3. Then again his reflex and speed will increase again any they are going to be usefull against ten tails . As again as told during naruto traing as sage one does not get exhausted gets less injury while using the sage mode that going to be of benifit .
When naruto combines both modes his chakara will become double of that what now he has from kyubi .
Then comes the main question how can naruto get time to collect the nature chakara, then one thing comes to my mind in chapter path towards radiance it shown that all teams except that of garaa are heading towoards naruto at least they can buy some time for naruto if not defeat the 10 tails . Naruto has other friends so no need of saskue to be there to stop 10 tails for naruto to collect chakra
2. Naruto has recieved chakra from son goku and others bikini so one possibility was that he will combine all chakra with kyubi to create chakra of ten tails inside him but that's not possible as he is missing chakra of eight tails and one tail bijuu of garaa as he was not created when he fought as garaa is still alive
3. Last but not least naruto most famous Justuu talk no justuu or if he uses his sexy Justuu on ten tails and as he is bleeding through his nose seals him
I am not an expert this may have some mistakes but this is my observation