1) Any excessive details should be textured onto the model. In this case, every damn star in existance has to be flat lml
2) The mask actually looks really good for blockland style. I would suggest rounding it a TAD, but not overdosing on roundness. imo, just making the back of the 'mask' (as in just the face) extend a bit so it's wrapping more around the head would be a good enough fix. But you are the modeler. It's all up to you to find which style works the best.
Great job though anyways. It's a great start, first draft, whatever, and although it needs improvement, that's one step toward success.
