The Cell simulator has been build with runtime in mind and that's why it uses a coarse model for the cellular network.
So what you can do is define regions that can act as cells but don't have to be of a specific area type. For each region you can define available bandwidths, the delay model, and the re-transmission model, allowing you to mimic the behavior of a "real cell".
However, it seems to me that the level of detail of the transmission model isn't quite up to your desires.

I can further point you to the doctoral thesis of Robert Protzmann who developed the initial Cell Simulator as part of his thesis.

Thanks very much, Dear @schwepmo for these details.