It is quite easy to find out whether or not a given consulate is likely to issue a multi-entry visa. However a multi-entry visa could in theory be issued for a small duration of time (such as a month), which would make its advantage void for most practical purposes.
Does the EU publish any statistics on which consulate is more likely to issue a long term (6+ months validity) C visa? With that information in hand, one could choose a Schengen country to visit for seasonal vacations.