Image resizing: best practices depending on h5p modules

Hi everyone, 

I'm sure many of you are using images and testing resizing on all devices and h5p modules. The purpose of this thread is to reduce guess work by sharing current usage to determine best practices. 

I'll start with

Course presentation - surface mode - insert a drag and drop image background:

image: 580x 300 pixels

The drag and drop image takes up most of the slide. More importantly, when user checks score, we avoid the scroll bar but the Back and Next buttons remain active as they aren't covered up by the task. 

Does this correspond more or less with your findings?