The Home page is highly customizable with Collections. However, there are times users want to see everything in a single Space (usually the Space has a small number of apps and data).
Having the option to "pin" entire Spaces to the Home page just like a Collection would be great. Sure they could navigate to the Catalog and filter to the Space in question. It isn't a lot of clicks. But by pinning the Space alongside their other Collections, they can now mix and match a view that has all of their Space items as well as their individual Collection items.