As long as you enjoy it, you still have room to create without moving piles out of the way, can store it in such a way that it doesn't develop nasty odors or bugs and you can afford it -go for it. Have fun.
One thought, when you buy fabrics for stash, sometimes it's helpful to buy some of the coordinating fabrics also. It's so very annoying to dig a nice piece of fabric out and then can't match the exact shade of color and have to do close enough.