1)
Why does it say "mi'Kolos Mayim Rabim"?
1.
Rashi: More than the noise of the great waters that clamors against us, and the great waves of the sea, You are mightier, and Your hand overpowers them.
2.
Radak: Mighty waves of the sea are noisier than great water, and Hashem is mightier than the waves, and lowers them.
3.
Malbim: The sea, its water and waves (where they break, lest they pass their limit and flood the dry land - "Asher Samti Chol Gevul la'Yam Chak Olam v'Lo Ya'avrenhu" (Yirmeyah 5:22) give their voice to say that Hashem is mighty above. He conducts Ma'areches ha'Shamayim and general nature according to His will, and all is submissive in front of Him.
