Wind,
You know its those finicky laws of physics that you're up against. You can't have efficiency, deep bass, and small size. The Hawthorne Silver Iris are the closest I've found to having it all, but as open baffles they thrive in larger rooms, lots of of open space around them, and need to sit on the floor.
Like Bemo and Wolfy stated, even listening at low volume (like I do) the extra muscle improves control of the drivers and adds dynamics.
Good listening.