This issue can also be solved/exacerbated by the PC you are using.

I play with two PCs, one that is crappy and can only handle like a 4/10 graphics setting, and one that handles max settings. The max settings PC loads a whole lot more characters on screen and a whole lot faster than the crappy PC. I dont think I have ever been limited as to how many characters I can see on the good PC. On the crap PC I can hardly see anybody.