manning1,

Have you paid much attention to what products like Jamstix, EZ Drummer and BFD actually do? Each of them has various flavors of what you call the KEY ASPECT, with user defined fill points and such.

They are pretty sophisticated programs, come with killer drum sample libraries, and in the case of Jamstix, really require almost zero drum grid/horizontal box entry whatsoever. Pick some base patterns, tell Jamstix you want a fill at the end of the pattern repeat (say you have a 4/4 pattern repeated 8 times for a verse - tell jamstix to throw a fill in at the end of the 8 bars and there you have it.), etc.

PG isn't going to be able to implement something like this without lots of programming resources. I'd rather see VSTi support of Jamstix like products first.

If you don't have another host other than PTPA, it's pretty hard to evaluate truly how revolutionary Jamstix is in this regard.