Well, it could reduce load on your avr....but you have relatively sensitive speakers to start, so little advantage one way or the other. While I have added power amps to avrs, most of mine are fine without....and the one I have power amps hooked up to was just because I had some extra amps sitting around to play with
Not needed, tho it does add some headroom when I crank it hard, but I generally don't do that anymore...being nicer to my ears these days.