It's great that you're planning to get her a larger cage. Definitely a worthwhile investment! Critter Nation cages are wonderful and so is the Brisbane which is available in white, black, green, and sandstone. Both are spacious and really good quality. The Brisbane cage is on sale right now and they offer free shipping. After using the Pocket Pets cage for my little one, I decided to 'upgrade' to the Congo cage from Exotic Nutrition. It's very big but she absolutely loves it. It's easy to clean and holds a lot of toys, pouches, and an exercise wheel. A good rule of thumb is to get the biggest cage you have room for and can afford. Also, as you probably know, bar spacing should be no more than half an inch wide.
I'm sure your glider will love her new "home" and will enjoy having the extra space to climb, run, and play!
Happy Birthday to you!