We have the laundry prep area but that has been converted into pantry & there is no way the DW is giving that up. Laundry day is once every week or so. Usually it is a CG laundry but if a coin op laundry is nearby, better still. Use as many machines as necessary to do everything one time & it is all done in the least possible time.
Can't see the point in having an onboard washer & dryer. Capacity is next to nothing so laundry day is virtually everyday or all day if you let it pile up for a week. You can do alot of loads for the cost of the onboard washer & dryer.