I really like the illustrations and explanations. When can we expect the natural transformations chapter?
And also I think there is a small typo at the end of second to last paragraph.
"At the same time we have the category of groups, for example, which contains the category of monoids as a subcategory, as all monoids are groups etc.". The roles of monoids and groups are actually reversed - all groups are monoids, but not all monoids are groups.
I don't think you can learn your way to the cutting edge of science in a lifetime with project-based learning. In my experience it just takes too much time.
Same, but it's only natural after studying inner product vector spaces. Also being comfortable with some calculus is needed to be able to overlook the technicalities of this construction and focus on the actual idea.
"Clojure for brave and true" has in my opinion an excellent section on Clojure tooling in emacs (which I wish i read when I was starting out with emacs).