I'm with you on this - I totally judge writers on their icons. In fact, there are a couple of very prolific writers on a comm I read that I refuse to click because of their icons.

Mostly it's because I've learned that you're completely right - icon is as icon does. If it looks amateurish and half-ass, 9 times out of 10 their other work is similar. Now, this isn't to say it has to be A+, but if it smacks of idiocy, I'm not going there.