The parameters are simple and easy to tune.
While you may use a meshlight as a deforming piece of geometry, deformation motion blur is not yet supported and could provide incorrect results.
In creating a meshlight, you may see a material connected to it called PxrBlack. This material has no parameters and is designed to prevent the mesh from scattering light a second time from itself. This is done to provide something intuitive, not necessarily something physical.