Check out the
Cozy Academy.
Once you have absorbed all of that, refine your questions down and people will be able to give you more precise answers.
Other general advice:
Try to be original, and emphasize the personality of the model. I say, for the most part, stay away from studio shots (like most of those you posted), as they come across as fake and sterile. Themed shoots, outdoor locations, and site features such as a diary/blog and weekly video chat, all play to the fantasy of prospective members.
Look at other sites similar to what you want to have, and make note of what you like and dislike about them. Don't blindly imitate them, but rather borrow bits and pieces and build them around your own vision and creation.
Good luck...
ADG