Actually there is .training A bloodline trait is not easy let alone one that you're not even trained in (his was shoved in his eye socket with no training) and a very small pool chakra. Don't think his body could stand continuous use of the shanninggun and other jutsus trying to teach both students.
Really??? OK first summoning jutsu you know the giant mountainsized toad that Naruto summons on occasion? Second Jiryas training Naruto lost control of his facilities at one tail was severely impacted mentally at zero tales. After his training Naruto is able to stay in control for the most part for all of type one chakra cloak. And you can't really blame him for not being able to teach how to control a tailed beast because well ge had no freaking clue.
Also would like to point out that He taught Naruto the rasengaun you know the move that he spams every five seconds or so.
As for the third, what do you want? his options were A childhood like Naruto's or B The life of Garra
Pick which one would work better. He made best of what he could of a shitty situation.
Also would like to point out that the students weren't that great either. naruto didn't notice all these clones shared experiences for YEARS andMILLIONS of clones
. And of course Emo Saske is Emo
No one in that seris is above being hit with the stupid stick.