Musical Paint Brush Tool

I had mentioned this earlier, but giving some more thought to it..  There would be a paint brush tool, similar to photoshop and some painting program.. This paintbrush would have several 'heads' which could be picked..

First it could act as a musical paint brush, or erasure.. The different heads would be like only write/erase passing tones, notes withing the current scale of the measure or different scales or modality, random notes, notes only on a certain subdivision of the measure - (paint only on the 2 ands). You could also control the density of the action from very slight to full blast..