Yes, it's bigger than the First. It holds almost 2x as much, I think. I think that would be a great choice! Also, if you still are hoping for a color in the pink family, a PF-er named Beverly has a lovely Magenta box on eBay right now.
eBay: Balenciaga MAGENTA 05 Box pink hand bag - authentic (item 260032693487 end time Sep-24-06 20:22:45 PDT)
That's hands down my favorite Balenciaga color!!!
The Rouge would be a great choice, too!