1. Interrogation Method: To gather information about Pain, Jiraiya, from Naruto, used a unique method in Amegakure. Instead of resorting to torture, he transformed one captive ninja into a frog, threatening the other to reveal secrets. This tactic effectively immobilizes individuals, regardless of their strength or abilities.

2. Rasengan and Fire Release: Naruto's signature move, Rasengan, was taught to him by Jiraiya. Naruto added wind chakra to create Wind Release: Rasengan. Similarly, Jiraiya could infuse fire chakra into the Rasengan, resulting in a more powerful version.

3. Fire Release: Flame Control: Jiraiya used a powerful fire technique, surpassing Itachi's Amaterasu, in his battle with Pain.

If Naruto learned this technique, it would enhance his powers further.

4. Shadow Imitation Technique: Jiraiya used a technique similar to the Nara Clan's Shadow Imitation Jutsu. Mastering this would greatly assist Naruto in battles, such as his confrontation with Sasuke.

5. Barrier Ninjutsu: Jiraiya demonstrated various barrier techniques, trapping enemies and providing means of escape. It is puzzling why he didn't teach Naruto these techniques.