UE4 is designed to make games, so the idea is that you would create your own installer.
The xinput thing is that it needs a DirectX update.
In your situation Unity is easier to share a game really quick, but actual game development is not more artist friendly—working with assets and creating things like materials and lighting are way better for an artist in UE4, and things like Blueprints make it so that artists can more easily create gameplay as opposed to the alternative of coding gameplay.