Okehazama can be considered a masterpiece. 3000 men vs 25000, it can be considered a pea-sized Gaugamela. Oda was at his beginnings with his fights, and with only a handful of men, it took some time really before you could kill 25000 men. I mean, you entered the camp, but at least a slight portion of them would have understood what is going on, and surely they got prepared and started to fight them. It's basically impossible to slaughter 25000 without any of them realising. So, it took a lot of effort and skill to kill all those dancers.

After Okehazama, Imagawa's territories became relentless, and thus Tokugawa Ieyasu declared his independence. Ujizane, Imagawa's successor, did many mistakes, and this only improved Ieyasu's chances of winning.

Mount Hiei was a battle actually. The Ikko Ikki Sohei (monks) were skilled warriors, but the sheer numbers of Nobunaga made the difference. If it was equal, then I would have doubted a clear victory of Nobunaga.

Nagashino is one of my favourite battles. As a Takeda fan, Katsuyori was a total idiot actually in comparison to Takeda Shingen. He didn't listen to his commanders, most notably Baba Nobufusa and Yamagata Masakage, and he used the sheer power of his cavalry to attack the Oda lines. Nobunaga, apart from sheer numbers, had mastered the arquebus tactics, and deployed them in front of his lines. The massed cavalry attack stood absolutely no chances against those guns. 54 of the best Takeda generals died, and this spelled collapse for Takeda.

Oh, and Tedorigawa cannot be considered Oda's battle. The forces were commanded by Shibata Katsuie, who was absolutely no match for Uesugi Kenshin. Expecting an attack, combined with a skilled commander and experienced forces (Uesugi and Takeda fought every year...) were no match for Shibata.

Hope it helps.