"A PCB can always be improved" is the thing i learned when i further modify my existing freezed single layer PCb for lm4780.It has only 4 jumpers. 1 in +V, 2 in ground supply and 1 in mute circuit.
Rin1, Rin2 and RGnd will come on track side. And Ground connections for speakers will be taken from power supply board.
PCB - PCB layout
Parts layout - Parts layout