I already made a similar thread about this. Please, I need to know if this feature is coming officially. In Curtains/Start10 you could set a background image with different layers of transparency in one image. For Start11, right now it is only accessible through a workaround and it's annoying to go through the steps after each reboot.
Look at this example screenshot, the bottom area where the shortcuts to folders etc. are has 20 % transparency while the top area has 50 %:

It's a big reason for me to buy a license after my trial, as the plain-colour/single transparency designs are way too boring in my opinion