Try the Fulltone Fulldrive II...handmade since the sixties....amazing tone and versatility:

http://www.fulltone.com/stpframe.html

It has Volume / Tone / Drive / Boost

Boost is another boost on top of the distortion. Volume has a comp cut feature that allows the pedal to be a strait volume boost if you like the tone of your amp for a particular song...if you can get your hands on one...I highly recommend it. I played a friends...fell in love...and bought on eBay for about 120 bucks...best pedal I ever bought.