Auto focus is less than ideal. It can make sense in some very simple single-task pages, such as a login screen, where the ONLY two fields are username and password.
But on a page that is any more complex than that, it can be a huge accessibility hurdle. If, for example, you have a large complex form on a page with the first field being, say, 'ID' then a person using a screen reader would load the page and hear "Form. Field: ID". Which gives absolutely not context as to what this page is about. Ideally, they'd be able to first read things like the title of the page, introductory content, etc.
Some more reading on this: http://www.brucelawson.co.uk/2009/the-accessibility-of-html-5-autofocus/
As for usability, many people prefer to keep control over their own cursor. So while autofocus might be a usability enhancement for some, it can be a usability problem for others. So another reason to avoid the auto-focus route.
To go back to your question, note that you are dealing with hunt-and-peck computer users. They certainly exist. And we need to accomodate them. But not at the detriment of other users. ;)
What I would suggest is simply create a larger target area for them to focus into. Make the fields bigger.
Instead of the top 'standard', style it like the bottom.
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And added bonus is that this makes things a lot easier for those using touch devices.