You can now punt either the Event Browser, Viewer, or Timeline Window to a second screen. The Timeline window is the real winner here, as the extra vertical space is great when in expanded Component view. Additionally, you can now hide the Timeline Window entirely, if you're focused on logging.
Video Roles would not work in the same context. While the vertical role order for audio makes no difference in how it the sound plays back, forcing a Video Role order would very much impede the flexibility of compositing order of various elements like titles, overlays, effects, etc.. I questioned this at first, but it's a non issue.