If you want to have something with tone control rather than just a mid boost why not try the
AMZ Tone Control it's based on the Big Muff tone stack but with an added pot to control the amount of boost as well as the frequency it's boosting, I think version 2 would be best for what you need. You'd need a small boost section after it though as it will make the pedal loose some volume. Since it's from the Big Muff why not use the gain stage from that:
I drew this up as a daughter board but it should be simple enough to add it to an existing vero. Green wire is input, blue output, red 9v, black ground.