change the default channel from 1 to channel 6

The tx power of some TP-Link models is limited to 19dBi on channel 1
so we win 1dBi with the change to channel 6.
Also channel 6 is the least used channel with no overlapping.
set mesh wifi multicast rate to 12Mbit/s
remove commented config stuff from the initial wifi config
add ebtables rules