These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Understanding Comics
Sequelitis: McCloud seems to have concentrated his best ideas (such as the "big triangle") in the first book, with Reinventing and Making being less ambitious by comparison.
Uncanny Valley: The big triangle shows the varying stages of simplifying and abstracting a human face. YMMV on where the valley actually lies on it.