Well, I think the Radical Design Small Panniers are practical for a low-racer; however,, I think they are more practical and look better having shape as opposed to just hanging as shown in my initial photos below.

So, here are a few photographs with the pannier walls stiffened using Corflute [vinyl corrugated sign material].

I‘ve used the better part of 2 days in completing this project. With the pannier walls in place: I have a nice tunnel for the rear-facing camera [if I choose to shoot video with the panniers on]; I do not have to worry about my taillight being masked my the left pannier; the chain will not make contact with the right pannier; the panniers will not make contact with the rear stays. I fashioned a stand-off for the right pannier that supports its weight. I contact the right stay with a rubber suction cup. I can protect my paint at that point using protective tape. I’ll test ride soon and adjust as needed.

Here are some other views: