Well, there are various degrees about changing cage accessories.
What I usually do, depending on the theme I have in place and how many accessories to support it, the theme may last one week, two weeks or even up to three or four weeks.
-The fleece that is used the most I usually change weekly (s/a sleeping pouch and liners), I have although left for two weeks in a pinch (hectic schedule).
-I alternate two large floor toys
(Tree house and Noah's Arc), usually about every three to four weeks, but sometimes an addition week, depending on what themes I am working with. I have a large branch (fake) that I can change from horizontal to vertical orientation for changes.
-As for the rest of the toys
and accessories, I move some around weekly and switch out a few weekly within a theme. A lot of times I will start with a few activity stations after weekly cleaning and then add additional toys
during the week to provide the variety.
-Most of my themes morph and change slightly by switching and moving furnishings and accessories week to week and try to stretch them out. I do have some themes that are more limited to one or two weeks, where some others I have more options to carry the theme twice as long, but still have changes.
-I find that lately, I've done several non-theme arrangements, but some of the ones I use are: The Enchanted Wood, Secret Garden, Rainbow Adventure, Tropical Paradise, Pirates Cove, AZ Cardinals, Lady Bug Invasion, Day at the Beach (newest, but a little disappointed in the cage set for that one).
-I also have done Halloween, Valentine's Day, and Easter, I've tried to do some Christmas, but didn't have much, now I have a cage set, so hoping to deck them out this year!
-Currently, I kind of have a mix with a flower flare! Lol.
I'm always thinking up new themes, but really do not have room to keep all the stuff.