Python can certainly do that kind of thing in PPP as it now stands. The problem is really in the phrase "any aspect of a character". There are an infinite number of conceivable connections between pitch, volume, rhythm and attack on the Midi side, versus the thousands of joint+rotation combinations in a Poser character. A script with enough flexibility, controls, and switches, to handle all those possibilities would have to end up being a free-standing program as large and expensive as Poser itself. If you know which (few) connections you really want, you should be able to write a Python script fairly easily to make those actions happen. For instance, the right arm goes down to hit a tabletop each time the Midi file indicates a bang on the bass drum. Then if you want something different, you can modify one or two variables and re-apply the script.

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