I did the room decorations and the Christmas tree back in 2012 and I felt it was worth it to see my Mom's face when she entered the room and saw it all decorated. In 2012, the cost of the 2 things was $750. I just read through the room decorations for this year and it seems that it is a lot less than what we received in 2012.
As for whether it is worth it, that is a personal decision, but I did price out the items that I received with my package and found that it was about $75-$100 less than the package and I considered that to be the delivery fee and set up fee. I will advise that if you order the room decorating package, you will not be able to access your room at the resort (we stayed at DLH) until approximately 6 pm - they will tell you the time when you check in.
I was able to surprise my Mom by having her not go up to the desk with me and the first thing I said to the CM is that I was checking in and was having the room decorated and if my Mom comes up please don't say anything. The CM was great because my Mom did come up and the CM played along and advised that with it being Christmas time (we checked in on the 23rd) that it was taking a little longer to have the rooms ready so it was looking like 6 pm and hoped that wasn't a problem. I also played along realizing that was the time for them to decorate the room and said that was fine, we would go to the parks. When we got to the room just after 6 pm, and opened the door, it was truly amazing...our room looked like Christmas...