Currently the icon/image for resource is just an upload.
do people know that they have to edit it to specific size etc before upload. A more dynamic way of uploading an attached image is desireable, maybe reuse the functionlity in the media gallery for upload and edit .
This is just a recommendation as of course a larger image will look better than a much smaller one. It's not suggesting that people should go and find an image and then crop and resize it themselves - we do that automatically.