Actually XML::Simple has a very simple rule for determining whether to output something as an attribute vs a nested element. If the value is a plain scalar, it will be output as an element, otherwise it will be a nested element.
Indeed... Just FYI, a co-worker and myself were evaluating XML::Simple for producing XML and he had the impression that there was no way to do this. If you glance at the SYNOPSIS, and see this: 
'gobi'          => {
              'osversion'     => '6.5',
              'osname'        => 'irix',
              'address'       => '10.0.0.102'
          },

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you get the idea that there is no way to force address to be an element somehow.

I knew about ForceArray but for some reason, things didn't click for me until your post here.

regexps as "non-plain scalars"

I wanted to ease my typing. The standard "non-plain scalar" is this: 
mother => ['Mary']

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but I was hoping to get away with this: 
mother => qr/Mary/

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because it is easier to type and more readable (IMHO).

Any chance of converting a node whose value is a regexp into an element as opposed to an attribute?

Order of sibling XML elements

Now, one other question, we are producing XML based on an XSD. I am wondering if the XML has order requirements on siblings. In other words, I did the sample XML for the original topic in this thread in XML::Simple - 
use strict;
use warnings;

use XML::Simple;
use Tie::IxHash;


tie (my %struct, 'Tie::IxHash',

 family => { 
        name => 'Kawasaki', 
        father => ['Yasuhisa'],
        mother => ['Chizuko'],
        children => {
             girl => ['Shiori'],
             boy  => ['Kairi'],
            }
       }
);          
         
warn XMLout(\%struct);

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but while each level of the XML tree was accurate, the sibling elements father, mother, children were in a different order than I wanted them to be.

In reply to XML::Simple - attribute encoding, order of XML by metaperl
in thread A data structure for XML generation by metaperl

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