The most annoying thing of the wiki is how they insist on calling a character their full name, even when that name is a spoiler, see monkey d garp, monkey d dragon and Trafalgar D water law. Or soon to follow koizuki momonosuke and vinsmoke sanji.
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The apareance sections should just use pictures. Also the fact that even the joke characters get their own pages, where only pandaman would warrant one to count his apareances.
The fact that they recount all the facts of the manga for each character, and the often cited using of a lower quality anime image for the sake of color. The wiki is just poorly conceived in too many places.
I don't even see what is wrong with using full names, plus the wiki is not spoiler free. In fact it seems that everything about the wiki bothers you rather then fix it or discuss with these people. This kind of attitude is not unique, there's subborn people everywhere