To make a long story short, I had trouble fitting a rack to one of my bikes, the Tubus Tara and Ergo both fit poorly on my particular fork that has some odd characteristics, ended up ordering those Axiom front racks in desperation. I tried a hoop like you did but I thought it was too flexy, perhaps my materials were lighter duty than you used for a hoop.

So for a plan B, I instead used a brace that attached to the inside of the fork mid-fork mount, like a Tubus Duo uses. That was much stiffer. I think a hoop like you used is better if it is stiff enough, as in a crash I suspect that the inner brace like I used would put more stress on the fork than a hoop, but so far mine has worked well. I did have one low speed fall where the front wheel dove into some loose soil and both I and the bike went down, thus the weight of the front of the bike landed on an Ortlieb Frontroller which was attached to that rack, but there was no damage to the fork from that.

My fork is unusual that the upper rack mount is farther forward of the fork blade instead of centered on the blade like most other forks, the lower mount is also up higher on the fork and further back than typical, thus Tara and Ergo both gave me an upper bar that was far from horizontal. The Axiom rack is not quite horizontal but is is closer, so that is what I am using for now. I am still on the hunt for a front rack that I like better, but that is now a low priority as the Axiom has been adequate. I will be using the Axiom again this year.