I woudn't worry about that. Get whatever speakers that sound great to you and go from there. Jumping around from AVR to AVR isn't gonna give you much. I would definitely be worried about getting excellent speakers above all else. Stick with that 703 and drop as much money as you can on your speakers. You can always purchased a used external amp later, if you even find that you need one.

If you feel the need to purchase a new AVR, I will gladly take that 703 off your hands.