Just a quick follow up to show a crude way of getting this done by passing the order of the classes into the base class:

package Base ;

sub new {
  my $class = shift;
  for my $mod (@_) {
    eval "require $mod";
  }
  bless { steps => \@_  }, $class;
}

sub do {
  my $s = shift;
  print "hi from Base\n";
  for my $step ( @{ $s->{steps} }  ) {
    $step->do;
  }
}
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Then call construct new from a script:

my $base = Base->new( qw ( One Three Two ) );
$base->do;
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