When I finished creating the trees I added a series of planes representing the leafy and branchy canopy above the environment, which appears to be working rather well. I also had to go in and alter my UV maps o allow for nicer edges and details to my distant trees which were suffering awfully from pixilation. The renders below show a pan across the majority of the scene.
Before and after of the distant tree pane alterations
The panning shot across the scene
I am fairly happy with this scene for now. The video below gives an idea of how I wish the scene to play out, prior to the addition of Morrigan herself and her crows mobbing her in the clearing at the end of the scene.