This article proposes a theoretical paradigm encapsulating the interrelations of music arousal and emotional valence with four commonly-studied musical factors: tempo, preference, familiarity, and presence of lyrics. We first posit music valence-arousal classifications and descriptors in accordance with the Circumplex model and a combination of several existing arousal theories. The subsequent section encompasses concise literature reviews on each of the four musical factors based on their interrelations with arousal, valence, individual difference, music-listening and engagement-related factors, while proposing delineations on their methodological considerations and classifications. Finally, a novel theoretical paradigm of interrelations among the pertaining musical factors, arousal theories, and potential differential effects among extroversion and neuroticism traits is constructed with several gap identifications following. Nevertheless, we emphasise the need in accounting for the intricate interrelations among musical factors in order to avoid confoundments in future music intervention research, while remaining open to further refinements of the proposed framework.