The Second Phase

So I enter phase two of my writing non-career.
Many things have occurred recently that have conspired to incite this new leg of my journey.
In particular, I have have some agent feedback on The Commuters and this has provided me with that professional perspective that I've so long required. There is little to discern between the responses: the concensus is that my writing is powerful/very strong and my imagination is wonderful. But, these agents feel that they would have difficulty promoting some of the narrative themes that I have woven into the story.
In this way, phase one has ended: I am at last a competent writer with a sound grasp of the basic tools.
In phase two, I intend to bring these tools together into a page-turner.
(Often cited requirements for publication/representation are ability to write and commercial/marketable story.)
To this end, I have been re-re-re-reading Vogler and McKee and anything I can lay my hands on that might remind me of what a page-turner consists of. (In studying the novel structure, I have noticed, almost by way of post-mortem, that the first act of The Commuters is too long: McKee suggests that act one of a three act work should be approx. 25% of the work. My first act already weighs in at 30k and is barely half the way through. Given that I have outlined a 100-120k novel, I'm way over. This explains so much, and I can see how the story would excite more readers by culling huge portions of the first act. This reinforces my thoughts and demonstrates how all of my plot cookies have become swamped in non-cookie stuff.)
In this second phase, I will be travelling alone. It has been a tough decision to make, but I am certain it is the right one. Everything is down to me now and there is little that anyone can do to help me. (Although I am running a stream of ideas by work colleagues in order to guage public reaction and guide me to the heart of my new work. Crikey - the words 'new work' are terrifying. The blank page!)
Most importantly, I am thinking of my reader with each decision I make. This reader is different to the reader who might enjoy my lit fic. In order to get my head around this reader, I'm studying The DaVinci Code and Harry Potter and the Prisoner of Azkaban. I am searching for points of commonality - for shared techniques and approaches. I have found many already, and I shall post my conclusions over the coming weeks.