From the beginning here, it's been suggested that Start Date could be used to include only tasks that are ready for work (meaning, exclude tasks that aren't ready/aren't possible yet).
Examples: "Pay corporate Amex"--which can't be done until the monthly bill arrives (but which has to be paid in just 2 days!). Or "Call Mom for Mother's Day," which can only be done on Mother's Day. Or "Do weekend shopping," which can only be done on Saturday or Sunday.
If I'm one of those retentive types who prefers a Focus list limited to what I can actually do... the current Smart List date filter options don't work for me.
So here's my suggestion: 1) Enable AND/OR (aka ANY/ALL) filtering or b (the simple option) Instead of "No Date" or "Any Date" being mutually exclusive (i.e. radio button-style) options, make them inclusive (i.e. check box-style) options (renamed "No Date" and "Select Dates"). That way the user could choose specific Select/Before/After date options OR no date at all.