What defines the overall layout change on the ERJ 175 in relation to its configurations?

The overall layout change on the ERJ 175 is primarily defined by configuration options based on passenger count. This aircraft is designed with flexibility in its cabin layout, allowing airlines to choose arrangements that optimize for various operational needs and market demands. Configurations can vary depending on the airline's service model, whether they prioritize more first-class seats or a higher total seating capacity.

By having different configuration options based on passenger count, the ERJ 175 can effectively serve diverse routes, accommodating both short and medium-haul flights while catering to different customer preferences. This adaptability is key to maximizing the aircraft's utility across different airlines and routes. The integration of such varied configurations enhances the aircraft's appeal to carriers looking to meet specific capacity and service-level requirements in their operations.