My other grandmother was a Cronin from Glencar, she was born in Dromdarragh just to the north of Shronahiree.
I have a Breen cousin who I think is descended from your Breens. He'd be a great great grandson of Henry(Harry) Breen, David and Johanna's son.
When you look at the spread of Crones, the majority seem to be encircling The Reeks. Most of them, with some exceptions, seem to be within a couple of miles of the foothills of the mountains.
I know the area well, but I use the DCU site for the townlands I'm not familiar with. It gives a fairly detailed map of all the townlands and the topography.
https://www.logainm.ie/en/22184