since your post processing engine is looking quite capable, I was thinking about new features for Splash.
you must have felt all that buzz regarding 3D (stereoscopic) movies lately...
* ability to input stereoscopic (side-by-side) movies & process for output with iZ3D / 3D-Vision & older anaglyph technology.
* Real-time 2D to 3D conversion - i've seen some really impressive solutions available like 3Dfier directshow filterTridef 3D player, software accelerated Avisynth Script and also cyberlink announced similar feature for upcoming PowerDVD.
I think implementing 3D stereoscopic playback can keep splash glowing as an advanced HW accelerated media player solution.