To answer all your questions:
1, what renderer we are using
We are using both Cycles and Blender Internal. For scene render we use Cycles to get quick lighting and clean diffuse, and edge render are all finished in BI. We experience FreeStyle but it seems unfinished and more a less for developer not artist to use.
2, our workflow
We take photographs from our city to get enough details references and then use Blender to model everything in our comic for copyright protection. Then use OpenGL render to finish screenplay. Meanwhile we will use BI to get edge render for 2D artist for character reference. After these work done, 3D artist will render the scene in Cycles for solid color and 2D artist will put some touch via Photoshop for details fix. Well that's almost our workflow.
3, will this cost a lot of time?
For this first issue, we have been working for three months as we need to build everything. But once our models lib have been set and all of presents been designed, the next issue will be produced very soon. Just like TheGuardian mentioned, if once scene happened many times in comic like two person talking. This would be easy for us to make the background quick. The first issue is testing our quality, and the next release is to test our speed. I will share how much we will use for the next release. In order to make sure our drawing style stable, we only plan to use 3D to create the background. Most of the time people will need to enjoy the story and character not the background, and we don't want to lost the core of comic as a picture novel. But 3D could make our view more unique and high quality as well as effective, so we plan to stick with it.
4, how many people of our team?
we have 1 lead artist, 1 3D artist, 2 2D artist, 1 story and 1 R&D support, very small team.
We will release more in the future for our comic works. Thanks for all your comments