The D-28s and D-35s are pretty boomy, yes. They were meant to be. The whole idea of the dreadnought body was to provide enough power in the lower register for the guitar to hold its own as a rhythm instrument against naturally louder instruments like fiddles and mandolins and, well, you know, those drums that some idiot put necks and strings on.A lot of the smaller Martins are quite well balanced.
Peter.