I wouldn't worry too much about that. If that kind of behavior spilled over in to boards like Technical Discussion or Technical Support, you can pretty much guarantee they would be rapidly trashed.

I quite like allowing icons and emojis in the topic title. Any thread which needs to resort to icons to draw attention to itself is probably doing so because it is very light on meaningful content. The icons allow me to see instantly which threads I should just avoid because they are likely to be nonsense, and it seems to be a pretty foolproof method.