1) What is the proper relationship between intellect and emotion, [and] between the spiritual and the realm of action? How much emotion during the day needs to be expressed? How can it not hamper the functioning of the intellect?
2) Is it good to listen to soul-stirring songs which are calming? Or does it fool a person into feeling that closeness to Hashem can be achieved without hard work? Should a person who is more emotional refrain from it, because it will cause him to slacken off from Torah study and from pursuing his long-term goals, and the like? If it is a good thing, how much should one listen? Should a person set aside time for it, or can it be whenever he feels like it?
3) I would be happy if the Rav can refer me to any sefarim that discuss these topics.
Answer1) The intellect must be active at almost all times, and calm emotions need to be active at almost all times. That is true for one who already has a revealed, clear faculty of intellect and emotion. If not, it will depend on his personal level, and even more so, in his soul root. Emotions need to be awakened as necessary, in order to pull away from one’s bodily hold, but one should not excite himself too much, because this hampers the intellect. The same goes for the relationship between spirituality and action – it depends on his personal level.
2) Yes, one needs to be balanced through consistent and stable exertion. Each time, one should see if his connection to his intellect is strong, and see to it that he is not satisfied or serene through the good feeling of emotional excitement alone. One should have a set time when he listens to songs, and also at times when he feels the need in his soul. But it should be done with pauses in between, and with the awareness that it is only an external drive.
3) I do not know of an organized sefer on the topic.