I'm attempting to move our announcements reel from Powerpoint to EW.
I'm still creating the image in Photoshop and just importing the image into an EW presentation slide set.

It'd be great to have more control over resizing images.
E.g. Setting a pixel, inch or centimetre absolute size, not just dragging edges in the hopes that it lines up.

Otherwise, being able to set margins not just for text, but for images too would solve the issue.

Thanks for the feature request. Here are a couple things to consider that might help.
If they are full screen images, you can drag them into the left column of the presentation and it will create a new slide and make it the background. You also get lines on the screen that help you line things up using the mouse.

[attachment=1:1l9wkx6r]Screenshot 2018-01-16 11.09.41.png[/attachment:1l9wkx6r]
[attachment=0:1l9wkx6r]Screenshot 2018-01-16 11.17.53.png[/attachment:1l9wkx6r]