If you are using the same sprite on many layouts and it has similar properties you probably want to set the sprite on one unused layout and call it home. If just about every layout uses sprites with properties specific to that layout then you probably don't want to set up a special layout for them.
The sprite shapes get merged either way so don't be concerned about memory--just do the best organization you can from the programming perspective.
Just my 2 cents.
yours
winkr7