"Red" flags (spam offensive) mark content that defaces and tarnishes the orderly presentation of the site and should be handled rapidly.
However, there is currently no way to tell at a glance that there are red flags in the queue, but a small and simple change could ameliorate that...
To help draw attention to the existence of red flags as soon as possible, could the queue background color be changed to red?
It matters not that red may also mean "queue too large" (FYI for non-mods, the color currently changes depending on the size of the queue), since red would then convey the broader sense of "immediate attention required", which is the meaning the color red has in most situations.
Actually, any indicator would be good – this suggestion seems to me to be the easiest to achieve and the most obvious in meaning, but other ideas are welcome. For example, changing the color of the text used to display the queue size (although color combinations with various background colours may be hard to read).
The bottom line is anything that leads to red flags being dealt with more quickly is a good change.