OK, you have never seen full until you have been there at Christmas!!
We own at that time plus during the winter time, which is much quieter than Christmas. October is not high season so you won't have the issues that you do during high season.
We generally try to go to Aruba a day or two before our assigned check in day. We just rent from the Surf Club. Flights are also cheaper if you fly out on a Thursday or Friday.