We are actively working on the next version of the Compositor right now. It will feature a tweaked user interface that provides instant layout previews, more types of layouts including more interesting and dramatic layouts, and support for many more images in a single composition.
We are also working on another product — a companion product to the Compositor that can create compositions with layer masks and effects.
Here is a sneak peak of the next Compositor. Note that it is still a work-in-progress.