Heel clearance is more of a pannier issue than a rack issue (as some noted in the comments). Most high quality paniers have adjustable hooks you connect to your rack, and you can usually shift the hooks to provide sufficient heel clearance. This is something you should more take into account when buying paniers. Good examples of brands that allow you to set them up to provide heel clearance are Ortlieb and Vaudé. Both are rather high-end, but they are also nearly 100% water proof.
Regarding your comment about racks collapsing: If all you carry in your paniers is whatever you use during a workday this shouldn't be an issue for the first few years of use. I have had racks break, but only after cycling thousands of km on all types of hard surfaces with full camping gear.
I don't have any specific rack advice. I always just buy whatever the nearest bike shop to where I am is selling. I have good experience with Cordo, topeak and Bor Yueh rear racks and lowriders. Always the models mounted to at least the axle, I've never tried any of the seatpost mounted models.