Distribute openrw in a Flatpak
http://docs.flatpak.org/en/latest/introduction.html#reasons-to-use-flatpak https://github.com/flathub/flathub/wiki/App-Submission
I do recommend use AppImage, but Flatpak is very good.
Anyone is of course free to distribute the software in any way they'd like under the license, but I don't see much point in doing some official app-pak thingy at the current stage we're in.
from personal experience i think flatpak is better than snap, but flatpak is still not as good as appimage
As with any package distribution system, I think it's reasonable to just let the users of that distribution handle creating a package for it.