First, the curtain thing is really about separating spaces rather than using space well. You could bring a tension rod and a curtain to put in the "doorway" of the sink area. It's a good way to keep that area less bright especially when you might be the first person waking up in the morning and are looking to let the rest of the tribe get a bit of extra zzzzzz.
Pop up hampers can be really great as well. You can get them at the Dollar Store sometimes for a buck. You can put these under the sink area to get them out of the way and just fill em up. I don't use the hampers for laundry, but in stead for miscellaneous items so that things aren't piling up on tables.
Bring a ton of extra hangers. Hanging your clothes is MUST in a Value Resort. There is very little drawer space. I use the drawers for underwear, socks, bathing suits, and extras.
There are five in my family, so it definitely gets pretty cramped in these rooms. We use the space next to the bed furthest from the door (there is a wall right next to it) to store suitcases. People usually don't store stuff there because of concerns about getting on and off the bed. I say - climb on from the middle - you don't have to get on and off that many times! If you don't plan on doing laundry, I would just fold up laundry and put it in one of the suitcases next to the bed. This way you know right away what is dirty. If you can empty a couple of suitcases, you can pre-sort which will make getting laundry done when you get home a snap!
Since you have some room, bring some of those small plastic bins/ baskets/ pop up fabric bins to put on the table and sink areas. At the end of the day, you can instruct the family to drop cell phones, keys, KTTW, photopass, wallets, etc in the bin on the table near the door. This way you're not looking for the essentials in the morning - they're all in one place, nothing is lost, and you can get out the door without screaming at each other
Clothes pins are good for hanging wet bathing suits on the little clothes line in the bathroom.
Use the safe for storage, too! We put things in the safe that we don't plan on touching during the trip, but need for the trip home. Then just put a note on the inside of your door that says "CHECK THE SAFE" so that you won't forget before you leave. It also helps you on your last day to get everything else packed without worrying that you'll need to dig through your stuff to find your Magical Express passes or keys to the house once everything is put away neatly.
I probably have a hundred more, but I won't bore you!
Good luck!