Thanks for thinking with me on this topic; what type of custom component are you thinking of ?

To limit the output send out to SSIS you have to be as selective as possible on the SQLServer side ;
For example, you could also build a View into your database and query the view from SSIS ?

Create view FASTREAD
as
SELECT l_Shipdate
FROM dbo.lineitem_Has96Key

To my best understanding this is still the best and fastest way;
(In SQL 2012 there will be a new index type ; the column store index that significant increases querying of a specific column too ! )

Brgds, Henk

Instead of embedding sql query in the ssis package and even avoiding view to select required columns, can we create some custom components that just retrieves only selected columns(at design time).