That would be a cool feature request. I don't believe you can do that today but it'd be a good feature request for SolarWinds to consider.
Have you used the nesting maps feature? A thought is that you can layer your maps so that you have a hierachy to them. Then on your top level map, make the icons extra large so they are easy to see. The nice thing about this is that it would easily call your attention to the Big Red icon but also gives you an idea for where the problem is located.