>>1675710I definitely agree that you need the contrast of the plain app tiles, but I also don't like having many tiles.
As you can see in the imgur, only me and Haqua anon have custom tiles for some apps.
Even then, it's very limited because a lot of apps won't allow 3rd party apps customize their tiles. (and probably won't now that 8.1 rolled out) so we're stuck with only launching a few apps. (Metrotube, Nokia Music, UC bowser, etc.)
As for the solid color idea, I haven't tried it, but I don't see why it wouldn't work using skinery or Custom Tile maker. Use a white/black tile with only the logo of a phone and set it to dial. I don't remember if it'll have a black border or not, but it would definitely look neat.