For honeycomb, square and triangular lattices we consider the groundstate threshold p c of spontaneous absolute magnetization in iso- and anisotropic random + /- J Ising models from so-called uniform classes HC z , SQ z , TR z . The class index z ( ⩾ 1 ) gives a fixed number of so-called PAF-bonds on the plaquette perimeter. A PAF-bond is a bond which has a positive (P) probability p to be antiferromagnetic (AF) and the probability 1 - p to be ferromagnetic where p has the same value for all the PAF-bonds in a considered lattice. The non-PAF-bonds in the lattice are ferromagnetic. In [Achilles et al., Physica A 275 (2000) 178], for each of the uniform classes HC 1 , … , HC 6 , SQ 1 , … , SQ 4 , TR 1 , … , TR 3 we proposed a so-called basic minimal (maximal) model to obtain the minimal (maximal) p c -value in the underlying class. Moreover, supported by estimates from simulations, concerning these basic models, we gave presumably exact values for the minimal (maximal) p c . Here we show that the predicted p c -values are linked by meaningful factors. To this end, in essence, z -values ( 1 , 2 , … , 6 ) and coordination numbers ( Δ hc = 3 , Δ sq = 4 , Δ tr = 6 ) are used. Typical factors are ( Δ sq - 1 ) / ( Δ hc - 1 ) or z 1 / z 2 ⩾ 1 . Especially, the minimal model case, with its 13 basic models fits in very well. Furthermore, for in-between-models of a uniform class, p c is approximated by linear interpolation between p c , min and p c , max from basic minimal and maximal models.