  On the basis of the scaling approach and CORSIKA simulations data the radial
scale factor of lateral distribution of electrons in extensive air showers is
confirmed as potentially effective primary mass estimator, and its sensitivity
to hadronic interaction model is investigated. It is shown that improved
composition results both on average and event-by-event basis can be achieved
taking into account the universality property of air shower development
expressed by the relation between radial scale factor and longitudinal age
parameter. The enhancements of such a theoretically motivated tool for the
unbiased cosmic ray composition deduction in a wide primary energy range from
(multi-)hybrid air shower measurements of nearest future are discussed.
