Is there anything I can do about the mouse cursor speed in menus? In game it's fine but in menus it's just crazy fast on my high DPI Razer. The mouse speed slider has no effect on it.

Not 100% sure about brink, but this works for me in other games.

In windows, lower your sensitivity, and in game raise it. The game sliders only effect gameplay, not menus, whereas menus are effected by windows sensitivity.