You can't export your EQ/Tone settings from Poweramp. Feature request it if you wish. "Direct Vol. Control" allows Poweramp's volume controls in the Vol/Bal settings to change your system's volume. If things are very quiet, make sure that direct volume control is on, and the Volume within Poweramp is turned up (this should turn up the volume of your system too). If you change your system's volume, you will see Poweramp's volume control change too.
There is no 'Good' EQ preset. Different speakers/headphones need a different EQ to sound 'good'. You may want to tweak your EQ to try get a flat response from your sound system first, and then apply extra bass and treble on top of that with the tone/volume controls for your taste. There are many guides on the internet for getting a flat response, but basically, for each frequency band in your EQ, the volume needs to be the same as every other band.