This may sound odd coming from someone who is building a tool to automate content inventories, but I don't think you can—nor should you want to—take the human element out of content analysis.
The point of doing a content inventory is to set yourself up for an audit, or analysis, of the site. Using a computer to do what it does best—catalog data, identify patterns in data, process lots of data quickly—allows you to spend less time on those quantitative chores and more time on what the human brain does best, such as the qualitative evaluation that leads to a full-fledged content strategy.
Content Insight's CAT (Content Analysis Tool) is designed to do just that—crawl sites and return data in an interactive dashboard view (also in downloadable reports so you can add additional data if you wish) that takes the tedium out of creating an inventory and speeds you on your way to actually analyzing the content of the site.
If you haven't signed up yet for the sneak preview of CAT, there's still time. We'll be releasing the preview in the next few weeks and would love your feedback.