While I appreciate and encourage personal expression, it's also frustrating to me when people make things difficult to read for others. One of my biggest complaints is when there isn't enough contrast between letters and their background. Why write something that can barely be read? It happens a lot.

It's good to express your personality. However, when you make people struggle to read something, it comes across as... arrogant? inconsiderate? I'm not sure the right word, but I find it irritating.

Hindering comprehension is beyond mere aesthetics.