I had that problem with mineral blushes too. You might try a fiber optic or skunk brush. They have white hairs on the end of the bristles and pick up pigments very lightly. I have the 198 or 188 (cant tell as it wore off) from MAC which is pretty good though I think I should have got the bigger one instead. I also have one that is really cheap as it was on clearance from a mineral place that is closing but I have seen it at
Makeup Brushes: Fiber Optic Blush Brush - Silver
Though I think its a cheap looking brush and shoddily made handle (just a silver molded handle) its become my fave for applying once you get the hang of it. I love it though I will still need to find another one as I dont think it will last. I can see the hairs will eventually fall out. But it applies great for mineral blushes. I just tap a bit of blush into a glass bowl and dip my brush in.