remove tx-power... it's an advanced setting and of no use when you are troubleshooting basic functionality...
change mode 11g to "option hwmode '11a'" ( or AC i think in the gui )...
also...
just do 20 for now... no fancy stuff ok?
( probably remove no-scan too after you test with the above )
11g setting has known issues... see other threads for workarounds ( although 'b' was getting removed from master?... so i'm not sure if it will still work... but setting to b and allow legacy rates used to work for 2.4GHz )