Economical usage of colors:

Color separation is an excellent observation but better belongs to "color contrast".

Shame that the proposed solution has nothing to do with the "what would I do differently" part (especially that you criticize red color and then use it in your solution...) Comments from the teacher: I tend to agree with Nicolas. I do find many of your arguments sound. But the improvement did not correct the original color problem. In ways, the background graphics took too much importance and did not let the main elements of the interface stand out.

Background & foreground graphics:

Good point about the icons. Other comments are very average, but implementation is much more interesting. From the teacher: I think the background graphics takes up too much space. It is rare that one uses a photo for the entire webpage. Often it is sufficient to overlay a small portion of the interface over a photo. Again here the grey scale image was not corrected in the final re-design.

Color contrast:

Some good comments, but don't all belong to "color contrast".

The final solution is good, but the analysis and justifications are destructured and partly incoherent, which explains the average grading. Comments from teacher: your analysis is often more interesting than the solution. My suggestion for your lofi design: try to look at a GUI in distance and perceive the colors globally. Ask some friends to give you opinions about a design.