The only problem here is that the variations in the variation (!) are chord type triggered, so the same chord structure will STILL repeat the same pattern. It WILL be different from song to song, but within one song still be repeating....

A better solution (IMO) would be to allow velocity triggered variations, so as you play harder, the drums would not only get louder (as some arrangers allow) but also to trigger different tracks. Now place that velocity crossover point in the middle of your average playing strength, and you will ALWAYS get a different track each time you play.

Roland allow a certain amount of this capability, allowing you to switch parts on or off with velocity (as well as just make them louder/softer), but unfortunately only allow you ONE drum track, so you can only make it louder or softer. But it works well with guitar tracks, and a combination of this AND chord related pattern changes can make for a VERY non-repetitive picking or strumming pattern. Of course, it uses up Parts at an alarming rate, so with only eight style tracks, you have to keep the style very simple (at least in terms of simultaneous sounds).

But it IS one more way to squeeze variation out of shorter length patterns.