David: After God's Own Heart?

I Samuel 21-II Samuel
David is definitely imperfect and continually proves more so. He is a warrior and whether out of fear or as a battle strategy, he tricks Achish king of Gath with whom he hides out while Saul hunts for him.
David is angry w/ God for His punishment of Uzzah for improperly touching the ark of the covenant.
David commits adultery and murder. His son Amnon rapes his half sister and is murdered by his half brother Absalom who sleeps w/ David's concubines and strives against David for the kingship. David's son Absalom is killed.
Plague comes upon the people after David conducts a census of warriors. David is a violent, military king.
But David has a deep excitement for God, abandoning himself to his joy when he brings home the ark of the covenant. David also has a deep respect for Saul's family in spite of Saul's treatment of him. Perhaps his friendship with Jonathon is part of the reason David feels this respect that certainly seems otherwise unwarranted. He keeps his promise to care for Saul's family after Saul's death.
The winsome boy David determined to stand up for God w/ whatever he has, trusting God for the outcome, is slowly and sadly replaced by a man willing to compromise and ultimately virtually destroyed by the consequences of his actions.