I'm confused on why the value of an hour isn't just your hourly wage. If you value your time more, you'd be working less. If you value your time less, you'd be working more. Since you clearly spend exactly as much time working as you do, you value your free time that much.

It's a very complicated problem. Many people cannot work more/less than they do and yet retain their current job. And working to find a 'more optimal' job can be extremely costly. Also, as you note, different time might be valued differently. I can clip coupons while I'm tired from working all day, but I can't do more programming or research as effectively.

If it was more on-topic, I might expand this into a post...