4shorts,
As nice as yours is, (it's beautiful)
I don't think yours (resting on the back shoes) would work good on my driveway or the other neighbors I do, we have ramped up aprons to city side walk and uphill drives.
If you have your loader in float and have the weight resting on those back shoes as well as the front blade, once you went over the side walk (or any other big bumps or swales) the front of the blade would be up in the air.
Of course all you would have to do is roll your bucket cylinders forward so just the cutting blade was making contact, then it would follow any contour.
The plow I rigged to my 3 PT utilizes a chain to allow the front of the blade to truly float over the terrain pivoting at the rear of the A-frame just like when mounted on a truck. the trick was getting the right amount of slack in the chain so it would have enough downward movement but not so much to not allow it to be lifted when the 3 pt is raised.
Believe me I didn't have some great forethought on this, it was just the easiest way to put it together, it wasn't till after I started experimenting with it that I realized that's the only way it would work for my situation. As unorthodox as it looks, it has worked great, having a 6.5' power angle plow on one end and a 6' bucket on the other is just the cats meow.
I think on fairly level surfaces yours would be fine running on those rear shoes, and since your loader arms look very heavy it's probably better you spread the weight load like that instead of just all on the cutting edge.
But looking at the OP's first picture, it looks like if he just drops the loader into float, he's got the plow at a good angle just like it is and the rear of the A-frame would be high enough off the ground, with just the cutting edge contacting the ground and the loader in float it should follow the contour of uneven ground.
IMO he should be good to go.
JB.