Definitely user definable maps, including velocity offsets and scaling, and EQ sys-ex etc. is really needed. Nothing worse than having a dozen (or more!) styles from another manufacturer, and having to go into the kits after the conversion to do the EXACT same thing to them all!

Software like this is much more likely to be used (and sell well) if stuff like this is taken care of for you...
_________________________
An arranger is just a tool. What matters is what you build with it..!