I am kind of surprised to hear that your heavy webbing can be softer than DiveRite harness webbing. I have DR, it was utterly soft and sloppy, so soft that once wet, d-rings will not stay in place. Anyway, not all the webbing are the same. Different stiffness is one thing, I also notice different width even they are all classified as 2inches.
The stiffest webbing I have ecountered is from Piranha. It feels uncomfortably stiff when dry. Once wet, it is just nice. I would recommend it for cold water diving where exposure suit is thick, so when d-on initially (dry), it won't cause disconfort. This webbing is also true 2 inches (on the wider end)
I also have some webbing from DRIS. They are not too stiff, comfortable when dry even with t-shirt, but can be stiffer when wet. Still not bad, much much better than my DR webbing. This webbing is NOT true 2 inches. I would say 1.90 inches, well enough difference to tell from the Pirahna version.
Then there is the Halcyon webbing, which I like the best. Stiffness level is between Piranhna and DRIS, comfortable with t-shirt, but still stiff enough when wet so everything will stay in place securely. H webbing is also NOT true 2 inches tho. It is on the expansive side as everything else from Halcyon, but they last quite long tho.