Easy to drive speakers avoid low impedance and phase shifts at all frequencies and require an amp work less hard in general be it at low or higher volumes. So that is advantageous. They will also tend to sound more similar with various amps.
Whereas high efficiency speakers simply produce higher spl overall per watt. The advantage there is mainly going louder with a less beefy amp. Beyond that any thing else is possible including a frequency response that sounds better at low volumes…or not