Displaying that many large images in the notebook just isn't currently feasible. From what I understand the notebook represents and renders images in a pretty simple way. The kernel however is pretty capable of handling it.
Use semicolons like you have been doing. If you want to view an image, I would recommend resizing it before displaying it in the notebook:
https://reference.wolfram.com/language/ref/ImageResize.html
ImageResize[myImage, 500]
If you are going to be working with a lot of images, you might consider adding some code so that the outputs are automatically resized:
$Post = Function[{output},
ReplaceAll[output,
img_Image /; (Times @@ ImageDimensions@img > 640000) :>
ImageResize[img, 800]]]
