What would be amazing for game development is the ability to export the cutout animations in a file format that we can use in most game engines.

One famous cutout animation file format is the Spine File Format:
http://esotericsoftware.com/spine-json-format

To support this file format would make it easy to import the cut out animations in game engines that support Spine File Format:
http://esotericsoftware.com/spine-runtimes

I think it should be possible in terms of licence (need to double-check) as there are other desktop apps that export in Spine File Format.

Another good source of inspiration for the file formats to support is Dragon Bones,
that is an open source alternative to Spine:
http://dragonbones.effecthub.com/features.html
You can see that they have a few different options in addition to the Spine File Format.

Overall, Spine and Dragon Bones may be good source of inspirations in terms of features/designs as they are desktop apps designed for cutout animation :)

Hope that helps.