The ability to instantly change samples for Instruments 00 - 0F would be useful. The Tool could have a row of 16 buttons so that you can select/deselect which Instruments get changed. XFER’s Nerve VSTi has this kind of functionality, it’s a convenient way of generating new drumkits.
I think you might like how ST3/IT2/Schism take care of this. Something like this would be very nice to have. however, even having a script set cursor focus to disk browser and being able to up/down arrow navigate would be swell too.