Learning Chinese helps me improve my English because it gives me a new mindset of learning other languages.
And NHK offers a good TV program of Chinese. A Chinese assistant speaks perfect Japanese, which also encourages me a lot by showing the possibilities of mastering other languages completely.
But it is difficult to master English without the speaking with natives. I drastically improved my English while staying in the US with host families but my English severely deteriorated after I left the US and not using it for a while.
Some people suggest I take online eikaiwa schools but I will be a customer in the schools so it is a little different from real life conversations. As a result I cannot push the limitations in such circumstances.
So my motivations to improve English now waned and Chinese become my main focus.