Washuru
some suggestions -use that nara mind for fuinjutsu, it would be monstrous, make a seal that prevents people from viewing memories like the yamanaka. you will most like be in the ino shika cho trio as a team so you need some defense. -prepare to decieve everyone and stay in academy to revieve extra training so you can stay alive. -learn as much as you can im sure the naras have photographic memory or high memroy retention. maybe get ini to help you make a jutsu to speed up the mind processes with chakra. - maybe make serum that works has various bloodlines but expands your chakra and effectively makes you immortal?can have all major clans of shinobi nations dna in it. -constant expensing of chakra and control exercises even in class to increase reserves. -use earthly knowldge and ninja medical knowldge with guys knowldge to help make the best diet for a ninja in training. -learn taijutsu from guy as we know chakra actually conteracts most kf bodys natural deficiencies so you use gravity seals or weights. - learn to breathe under water or make a jutsu. - prepare for a scenario if your chakra is stolen or sealed, maybe make a fyinjursu to prevent this ir maybe a juinjutsu or something. - use yamanaka flower shop and nara funds to buy poisons and become immune. Maybe befriend anko and learn from her in the forest of death. -learn the sword as it makes sure your opponents is futher away from you. use that chakra star metal from the naruto movie. -learn samurai abilities. -trainjng with guy for the eight gates is key. Basically train your base abilities to kage by the chunnin exams and during narutos training trip you can experiment but also expand abilities and learn sage mode. Give the mc a objective maybe establishing a United Nations in the shinobi world founded by himself uncluding all villages where you establish human rights and trade routes etc. you can also make a spy network. you can also use seals to make sure whoever is in power diamyo or kages are always doing their job to the best and are loyal to you. I feel like for pairings for the mc you have to have a strong woman that can challenge and guide shika. maybe kaguya as she can help him against otsutsukis. She isnt even the strongest in her clan so you should consider that. If not her then maybe temari if uou build the romance and character more. So far its good, good luck