Gemara:


A Man Among Men
(condensed from Ein Ayah, Berachot 5:30)

Ein Ayah: The righteous Chana’s whole goal was to have a son come from her who would save Israel and lead them on a path of life to make them Hashem’s Nation, now and in the future. Individual leaders can have a special characteristic, whether in the realm of the spiritual or the physical. However, Chana saw that the nation needed a more all-inclusive leader. This is only possible if the leader possesses diverse characteristics that are generally found among various different people. Then he can stand up to the diverse challenges of the generation and independently lead the collective nation. This is what is meant as a man among men.

An Offspring Who Will Anoint Two Men - Shaul and David
(condensed from Ein Ayah, Berachot 5:31)

Ein Ayah: We have explained elsewhere that a nation must be concerned about its welfare in the present and in the future. Usually when the two needs collide, each one is weakened by the influence of the other. The ideal situation is for each one to be strong as if the other does not exist. That is the characteristic that Chana prayed for in her son. He should be able to impact on the present as if there was no reason to worry about the future. This is illustrated by Shmuel’s anointing of Shaul, whose kingdom was to be short-lived and served only the needs of its time. In contrast, David’s kingdom is eternal and thus was complete in the area of the nation’s future level. This, according to this opinion in the gemara is the intention of the phrase, an offspring of men.

An Offspring Who Is Swallowed Up Among Men - Neither Tall nor Short, ...
(condensed from Ein Ayah, Berachot 5:33)

Ein Ayah: In order to impact on the generation, the leader must be close enough to the level of the generation in order to make an impact. Therefore, Chana was willing that her son’s personal shleimut would be compromised in order that he be integrated enough to be accepted. That is why she prayed that he physically be very average so that he could more easily make a lasting impact. It was not sufficient to her that he be impactful on the minority of people who would share his unusual characteristics.
[Editor’s note - Shmuel, who was brought up in the Mishkan, could hardly be described as having an average type of upbringing. Rather, the thesis seems to be that since spiritually he was to be exceptional, at least physically he should fit in.]