I agree, give the back copy the same treatment as the text on the front.
You said your brother creates music via computer software, as in lounge, trance, melodic, atmospheric ?? I’m guessing ??
I really think that the blue covers fit that genre more so than the white and black covers.
The B/W covers work very well in their own right. They are dirty, appealing, and interesting.
If I had these covers this is what my next step would be: again .IF they were mine hehe.
BLUEcover // I’d take the sharpen tool and set the opactity to about 60-70ish range. And sharpen a few hard lines to create a TINY bit of contrast between the blended blues. This would create more depth in a 3d atmosphere. The sharpen tool can create some nice effects if you play it right.
BWcover // use the paintbrush tool set to overlay, and add some very very light colors over the textures to make it pop just a bit. There’s already ALOT going on so you don’t want to “muddy” it up anymore.
Anyway, I like em.