yeah it was definetely an in depth response, and I probably should have given some reasoning behind my answer (and include that I'm a 12th gen cavalry lancer who has always had shield/1h as well, except for 1 gen).
Having more riding than your horse requires is nice for the little extra speed/manuever, but it's not worth giving up that 3 extra strength, and 1 extra power strike you can have instead.
as a 1h/shield/polearm/riding build, I would always recommend maxing WM (or almost maxing) and max athletics, riding and power strike. You only need 4 shield skill max for riding, and you could even get away with 2 or 3 if need be (although I would recommend against it). And ironflesh is certainly nice if you can afford it, but I'd give it up in a heart beat in order to max the other skills (besides shield).