We saw the deluxe units last year and are staying in one in a few months. As long time owners the differences we noticed in the downstairs unit were these.
The main bath is now double entry, from both the guest bedroom and living room so the people in that bedroom do not have to leave it to use the bath.
They have removed the overhead cabinets between the kitchen and living room making it more of an open floorplan rather than a pass-through.
The spa room, only in the downstairs unit, has a much more modern spa tub than the 20 year old models in the older units. I also recall the room being drywalled (hopefully with cement board) rather than the wood paneling.
Also, all the TVs, furniture, bedding, kitchen appliances, etc is much more upgraded that the old units. And all the deluxe units I saw seemed to have sidewalk level entry doors rather than the sometimes high porches in the older units. Of course, the older units have been undergoing renovation for a number of years and how nice and modern the unit is depends on which one you get. The deluxe units cost a few more points, but I think it's worth it.