Is that a homemade rack on the Windsor? Interesting.
I'm going to swap racks hopefully this weekend between a road bike and a different rack I currently have on a MTB and see how far that will set the bags farther back. I currently have a small pair of Cannondale bags with the zipper-to-tuck bottoms on them. I also have a Raleigh branded set of panniers (no idea if they were branded for or made by Raleigh, nor how old they are). I'll see how far back the bags will go once I swap racks. I know that on the Schwinn I would have had to hang the rear hook of the bag off the rear of the rack to give me enough heel clearance. Maybe I should look into swapping cranks, currently mostly have 175's, might check if I have any 170's to try out, but I'd probably have to go down to 165's to see any appreciable heel relief.
I'm also going to have to look at my road bike options again and measure some chainstay lengths. I've currently got a late 80's Schwinn LeTour and a Univega Sportour, both in ridable condition. I've never really compared their measurements. I've also got a Motobecane Grand Jubile undergoing a major overhaul/rebuild that when done will bump a couple of other bikes out of the garage and onto the local craigslist. I was thinking the Moto might work as a light tourer.
Sizing wise, I wear 29"-30" inseam length pants, so I am more torso length and less leg length. Bikes with a 56cm top tube seem to fit me best, and those with 32" or less standover seem to feel better as well.