Quickform Types Definitions or Examples
I usually find more detailed examples by looking in the CiviCRM code, which is exactly where I found the answer to the " i do not want time" question a while ago :-)
As I found it I can share it with you: 

$this-&gt;add('datepicker', 'activity_compare_date', ts('Comparison Date'), array('placeholder' =&gt; ts('Compare with')),FALSE, array('time' =&gt; FALSE));


And yes,it would be ideal if all these examples would be in the developer guide. So I would like to invite you to the next CiviCRM sprint to make this happen :-)