It would be really helpful to have a possibility within Blender to bevel selected edges or faces instead of the whole mesh.
Changeable values should be:
- additional extrusion during bevel (number in Blender Units, 0 for no extrusion)
- inner offset (size of the new inner polygon)
- number of new edges (1,2,3....) during beveling (currently only 1 edge is implemented)

There is a external phyton script which handle the need to have a possibility to bevel a edge or face, but is currently available only by the help menu and does not have the other options.