Macro-wise, it would be like an unwieldly minimap which already exists so people can get a sense of where the enemy is moving. With a giant screen, information is not focused on a small area, so you are limited to your FOV. Minimap which shows unit strength in terms of armor hp or shields as well as placement would be ideal information.

Micro-wise, it would be like sitting in front of a giant text display looking at a whole book. You still have to focus on a small section to read it.