Side skirts, if I was you I would go with the kaminari ones for the sedan. I think they would look good cause you got two openings on each side of the front bumper. The side skirts have two openings on them also, keeps the idea consistant.
http://www.kaminari.com/products/00Focus4DR.htm
As for the rear bumper, maybe the Wings West 'Avenger' one cause it has that 'mesh' like the middle of the front bumper you have plus it's a distinct one like the front you have. That or possibly maybe the kaminari full back bumper, it's got a center exhaust outlet though. The 'air dam' on it might flow good with the one on the sides of the front bumper.