Guys, get your facts right. Designer is priced at $594 if you are a Unity Pro user and Designer Lite is at $350 for everyone
Now about the "closed-source procedural textures", we heard your feedback and are actually preparing a reupload of all our textures which will now include the source files, allowing you to open and modify every texture you bought. This should be live on the asset store in the coming weeks / before the end of the year.
About B2M, it's really easy to create your own B2M with Designer after a few weeks studying the tool, so with a bit of work you won't have to buy it at all