minstr and maxstr are well defined for qw( Porculus mr_mischief metaperl ikegami ). meanstr is not. (The median though could be defined for odd-sized lists of strings.)
The thing is that Perl has different comparison/ordering operators. So there are two natural ways to define min and max in Perl corresponding to the two sets of ordering operators. Had there been only one version of "greater than" then I figure there would have been only one function for min resp. max.