Psalm 81 - This Psalm speaks of worshipping the Lord, not just how people should sing and praise, but also how they should come to listen. It's noteworthy to see in verse 11 that the people wouldn't heed God's voice and then in verse 16 God tells them what He would have done had they obeyed Him.
Psalm 88 - This Psalm is a song of lament. The Psalmist cries out to God regarding the trouble Israel is in. It's similar to Jerimiah's book of Lamentation. Yes, there is room to share with God the hurts you feel and to cry out to Him for mercy and relief.
Psalm 92 - Now, this Psalm is a song of Joy! Here the Psalmist expresses gladness and pleasure in all the good things God has done for His people and the way these people will continue to praise the Lord even in their old age. When was the last time your prayer was a prayer of praise?!
Psalm 93 - Right from the start this Psalm speaks of God's control and authority from eternity past. The Psalmist uses the oceans as an example of God's strength. People are impressed with the power of the seas, but God's power is infinitely greater.