Answer:
Cubist style artwork actually uses manipulation of depth, and if you'r goin for a 2-D look, depth, really is not a a problem. There are lots of great works or art that don't have much depth, it depends on you personal skill and preference. But if your working towards an assessment, try looking up Cubism or 2-D work, that may help you gather some inspiration.
Hopefully that help ya!
Explanation: