Why isn't Day 2 good?

The firmament is the interface between the waters. It is firm water or ice.

The word for ice also means 'make bald'. Hair represents authority. The taunt to Elisha "Go up old bald head" was a taunt that he had no authority.

The leper shaves his head as a symbol of the Father leaving the Son while on the cross.

The separation of the Father and the Son was the real horror of the cross; not the physical torment. With the Father gone, and the Son made to be sin, where was God on earth? This is the great desolation. How could the earth be any more desolate than this?

The day of the cross is the great and terrible day of the Lord. It is great because of the reconciliation wrought, but it was terrible because God was torn.

Day two was not a 'good' day.

As a table of contents entry for the rest of the Bible, day 2 points to the Noah story. In this narrative it grieved God that he had made man. It was not a good day.