Originally Posted by N.Stocks 
But with just organizing them according to date, means that you will always need to search using the search tool...
This is what smart folders are for. Your search criteria can be very selective, and you don't have to re-execute the same search over and over. If also allow you to perform an impromptu search over a date range really quickly.
Doing this way reduces the amount of thinking over the long run because the thinking (keyword assignment) was done only once, right at the beginning.
If you think about it, a deep folder hierarchy is a lot like a keywording scheme with the exception that a photo can be in only one folder. What if the photo is of a bug
on a flower? In which folder does it go? And once you decide that it goes in either "bug" or "flower," how do you remember which one when you go looking?