I don't really want to spend the gobs of time that would be required to create the ideal SRS system (good workflow, adjustable importance, parameterized sets, etc, etc) especially since so much pretty good stuff already exists. But if someone else feels inspired to take on that task I'd be glad to help out however I can.

Anki is open source and allows for plugins. If you want to help making Anki a better SRS system the road seem clear.