Image / Content Alignment & Custom aspect ratios

We are currently using 16:9 content onto a 16:10 projector. If the computer (and therefore presenter) outputs 16:9, the projector will centre align the content with black bars top and bottom. If the computer and presenter output 16:10, but the background image is 16:9, presenter will align the image center also.
I would like to be able to control the alignment of background images and videos, to top, middle or bottom as well as the current scaling options.

Also, if there was a way to control the alignment of the entire slide within the output display, this could be useful. (e.g. if creating a 32:9 slide, but the output window is 16:9 we should be able to control how presenter will align the slide within the output display.

Lastly, custom aspect ratios for slides would give us a lot more control over the size of the slide within the display output where we need to adjust the output size without changing the output resolution.