Right now each substance tool (Designer, Alchemist and Painter) has it's own library. I have an idea where all Substance software connected through Launcher or just library.
This will allow to have all materials, grunge maps, tools etc in one place, what is obvious, and this would be convenient for a user. For example if I load a material I have to put this material inside SP and Alchemist folders separately.
Also, single library would connect materials across Substance software, for example if I load a material from Source, modify it in Alchemist, save it to my library inside Alchemist and use it in SP directly. Super useful.
Else, there are a lot of content missing in SP from SD, like quantize, emboss, skew and many more! Single library would open all filters and content from SD to SP. There might be problem with utilities that cannot be cross-used in SP and SD, but tagging will solve this.