Do you think music should be secondary to the imagery or should it play an equally important role in telling the story or portraying the mood you are shooting for?
I think it's dangerously limiting to think in these terms! Music is a filmmaking tool, with many potential roles/uses and thinking of it as always secondary to the visuals or always equally important limits it's usefulness/effectiveness and therefore limits the filmmaker. Incidental music is often used to "paper over the cracks", for example, smooth out an otherwise clunky visual edit or help maintain a continuity. It's also used to accompany/enhance the visuals by altering an audience's perception of the pace of a scene. It's also used as a primary storytelling tool, to create a feel or emotion and commonly it's used as a combination of all these things.
There's also more advanced uses of music which are generally avoided by indie filmmakers, either because of a lack of knowledge and/or because it's often difficult get it to work as intended. For example, a side effect of incidental music is that it tends to draw an audience out of the reality of the scene and advanced filmmakers sometimes use this to their advantage, to create an additional impact of reality from the contrast. Two good examples of this are Saving Private Ryan and The Return of The King (LOTR). In SPR, music is used before and after the Omaha Beach landing scene but stops and is conspicuously absent during the scene itself, the contrast between music and only SFX dramatically adding to the impact and sense of reality. In ROTK, the music abruptly giving way to dominant SFX exactly on the frame of impact (Theoden's army crashing into the Orcs besieging Minas Tirith) creates a contrast between the glory of the charge and the horror/reality of battle. Another good example of advanced music use is the antonymic use of music, music which contradicts the visuals (rather than supporting or accompanying them). In this use, visuals tell one part of the story and music tells a significantly different part, neither on their own tells the whole story but together they tell a wider story. A classic example of this is the use of Barber's Adagio in some of the scenes in Platoon, where the visuals and sound are fast paced, high action/drama and tells the POV story of extreme violence, cruelty and the abuse of power while the music is slow paced and serene and tells the story of loss and the futility of war.
As a generalisation, too often indie filmmakers use music just to "fill in the gaps" or "paper over the cracks" and are too influenced by what they like personally, rather than fully appreciating the advantages/disadvantages of using music and using it to it's full potential.
G