Option to choose image size in Cover and Image block

When Featured image is chosen for Post, full size image is linked.

When Cover or Image block is inserted in post or template and set to use Featured image, full size image is used. This happens even if actual view of image is much smaller.

For Image block there is option to additionally choose image size used so user must be aware that his site unnecessary loads full size images just shows them small and use this option to change that.

Form cover block there is not option to choose image size. Full image size is used each time.

This is huge waste of resources on site. The first rule of using images is to reduce their pixel resolution to match actual size that should be displayed.

User interface should warns users on this and help them easily notice discrepancy in physical and displayed image size and fix that.