What is the authenticity of the hadiths narrated concerning the immense creation of some angels, and what is the wisdom and benefit of their creation in this size? And is their size commensurate with the cosmic distances mentioned?

You mentioned three hadiths about magnificent creatures: the first about a mighty rooster that glorifies Allah, the second about a great angel who says, "Glory be to You! Where were You, and where will You be?" and the third about an angel among the bearers of the Throne, the distance between whose earlobe and shoulder is a journey of seven hundred years. All of them have authentic chains of transmission.

The benefit of creating these creatures is that all of Allah’s actions are based on profound wisdom. He does not create anything in vain, even if some aspects of His wisdom are hidden from people due to their limited knowledge. It is incumbent upon the believer to have faith that Allah is Wise in His actions and does nothing except with wisdom.