Any pattern stuff would also need the capability to play ahead of time, laid back, etc (nudge) and have shuffle settings, etc. Real musicality against rigid lego only grooves.
But yes, patterns with pattern variations are very welcomed, including editors and machines - with drag and drop and bi-directional editing (yes, new API's). Propellerheads Reason or Tracktion i.e. are a good start to look into this. Bring it to the next level.