meta quote ops will help a lot, especially qw.

I'd definitely prefer push (inverse of pop) for appending arrays and it's friend for prepending arrays, unshift (inverse of shift) .

Slight improvement to your last example:

  push(@inputfiles, qq{$inputPathPrefix/test4.xml});
  push(@inputfiles, qq{$inputPathPrefix/test5.xml});
  push(@inputfiles, qq{$inputPathPrefix/test6.xml});
  push(@inputfiles, qq{$inputPathPrefix/test7.xml});
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Better (IMO):

  my @files = (qw/test4.xml test5.xml test6.xml test7.xml/); # assumin
+g you know $inputPathPrefix will be the same for all of them
  push @inputfiles, @files;
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The rub with qw// is that there's no variable interpolation. This means the following is treated literally,

  my @files = (qw{$inputPathPrefix/test4.xml $inputPathPrefix/test5.xm
+l $inputPathPrefix/test6.xml $inputPathPrefix/test7.xml});
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is equivalent to:

  my @files = (q{$inputPathPrefix/test4.xml}, q{$inputPathPrefix/test5
+.xml}, q{$inputPathPrefix/test6.xml}, q{$inputPathPrefix/test7.xml});
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There is probably a lot of ways to do this idiomatically, the above is just an example of where I'd tend to go with it.