20 or so years ago, when I spent more time in pedal forums than anywhere else on the net, I had this idea. I thought it was an original idea... I had a friend helping me design the circuit. It had 3 clipping options and two gain ranges but the real reason I had the idea was to put a true parametric mids control on it. A "full one" with sweep, Q and level! We were actually going to build a few, send them to some of the big name reviewers for some street cred, then go into production. I was convinced it would be THE best OD pedal ever because... low or high gain, 3 clipping choices, and of course, complete control over where your mid boost was, how wide it was, what frequency it was centered at, and how much of a boost.
After over a year of talking and actually doing some circuit layout, we discovered that someone had done the sweepable mids control on an OD pedal many years before... apparently it never really caught on so they quit making it.
Here is the good part of this story... BYOC recreated this as a kit, given how great the idea of sweepable mids was, and as of the last time I looked, was still making the kits. Here's a link to their clone of the original (Pearl) and some potential mod ideas.
BYOC Parametric Overdrive