It is often heard that Raavan was one of great person to live. He was expert in Vedas, and other scriptures. He was sitar player. However, I'm not able to find any scriptures' details to ascertain this. So far, I have found that Raavan was adharmi right from birth, perhaps the most evil Rakshash ever born (although not the most powerful one : Valmiki Ramayan, Uttarkand, Ashtam sarg, Shlok 24)
For example, Raavan had no knowledge of Bhagwan Shankar, even after receiving boon from Brahma. His ignorance of Shiva's great powers and that he was savior of Rakshash clan is clearly exposed in Valmiki Ramayan, Uttarkand, Sarga 16. How could such an ignorant be a great scholar?
My question is not limited to just ved gyaan. What were his dharmik or positive qualities if any (besides his tap for brahma and Mahadev, and a fierce warrior)? Did he ever help someone or did positive acts? Thank you.