First welcome to the forum. Secondly, I have been looking at the magazine issue you are discussing for the longest time. I can't tell you how much I have read and researched. My conclusion is that for what ever reason it is the design of the magazine. Some of the research says that this is somewhat common in a single stack magazine and also common in 1911 designs do to the angles. I will attempt to attach something I found and hope it works. It really explains this well. I really have to manipulate the rounds and tap to get them to seat well. Even then if you push with your thumb you will notice that the rounds still tend to nose dive. You are 100% correct. I also feel that many of the issues are not the result of the Solo but the design of the magazine. If you research nose diving, you will see The Solo is not the only gun having the same issues. Almost all the small 9 mms have similar issues regardless of the make (just google nose diving issues and you will get to every forum of every gun and everyone says the same thing...it ain't a Kimber issue!!!.) it is a design and physics issue. Also, in my research found that the heavier the grain the more the shape lends to give support to the upper round. Hence, Kimbers recommendation for heavier round.
That is why it is recommended to lock the slide open, and use the slide release lever to load the first round in the chamber. For what ever reason, (the force of the spring) it chambers well and viola no problems. At least in my experience. As awkward as it appears it works. There are many videos on you tube showing how unstable the rounds become after the loading of the 5th and 6th rounds or 7th and 8th in extended in single stack magazines. Again, research magazine nose diving. As for myself my Solo works well. Attached are the photos of how the rounds sit in the magazine. This is the exact design as the Solo mags. With time I find that the rounds do seem to seat better. Maybe it is some relaxing in the spring in the mag.
Hope this helps. By the way, my lips on my mags don't seem to be that extreme.
View attachment 375