I'll be the first to admit this looks cute, and also to admit there is value to cute. With that said, this storage system will make it very difficult to use your washi tape. Why?
Washi tape is what I call an "in hand" product. It works best when you have it in your hand. You want to pull out some tape and then lay it out on your project before you pull out a little more.
With washi tape on a dowel, you would either have to take it off the dowel (pain in the neck), or pull off one strip of tape at a time, then go back to your project and lay down strip, then repeat if you need more. Frustrating and annoying.
As you're choosing organization products for your supplies, consider how you will use the supplies. You'll make better decisions. use more product and have more fun crafting.