This paper discusses the ergonomy of the visual formalism proposed for a refinement of object oriented programming termed «colored object programming". A number of principles are first proposed (ex. : unique source, unique destination, non ubiquity,...). With the help of examples, these principles are shown to mould both the color graph formalism and its specific instantiations. These principles may be transgressed to yield new propositions : corresponding advantages and drawbacks are discussed. Two important alternatives are then examined : cartesian type representations useful from a pedagogical point of view, yet obviously unmanageable in general ; and what we call «color higraphs", obtained by using insideness in place of connectedness for reflex transitions. Except for a few details,this transformation remarkably leads to the David Harel's notation (i.e. higraphs or more exactly, statecharts) for -a priori, non object-oriented- state-transition systems. To conclude, we propose to center the planned programming environment around our visual formalism, and to open it to alternative representations depending on the programmer's task (as a writer or a reader).