I usually find that the images that users use on forums, especially when they are somewhat odd-looking, really reinforces who is saying what. Maybe there is so

I usually find that the images that users use on forums, especially when they are somewhat odd-looking, really reinforces who is saying what. Maybe there is some scope for taking distinctive glyphicons from a project like Bootstrap and displaying it next to the username. And combine this with your color scheme, I think it might become easier to keep track of threads. Although, some people may not like the icon associated to them.