Jeremiah 17:9
The heart is deceitful above all things and beyond cure. Who can understand it?
The heart is a thump thump organ, nothing more. And you beliefs makes you no more a witch, than me a villain for playing the evil guy in games.
Jeremiah 17:10
"I the LORD search the heart and examine the mind, to reward each person according to their conduct, according to what their deeds deserve."
If the heart was truly evil, why would the Lord search it?
I believe the context is more warning against letting your emotions lead your actions. We see it on the media all the time; person is proclaimed guilty before all the facts are known of the case, because said person's skin color is different, they smoke a joint in their home, they have tattoos... etc...etc...
As for Bible Verses about goodness of emotions;
Matthew 6:21
For where your treasure is, there your heart will be also.
Proverbs 3:5
Trust in the LORD with all your heart and lean not on your own understanding;
Proverbs 4:23
Above all else, guard your heart, for it is the wellspring of life.
Psalm 19:14
May the words of my mouth and the meditation of my heart be pleasing in your sight, O LORD, my Rock and my Redeemer.
Psalm 37:4
Delight yourself in the LORD and he will give you the desires of your heart.
(by the way so there is no confusion...this is SCN, and it is so easy to take only one verse and turn it on it's head.)