First of all, let me just state that I think profiles and profiling, although a scientific process, is still a very subjective endeavor. It still relies heavily on how the amp is set and how the speaker is mic’d and each of the individual parts contribute to the overall outcome. And since tone is so subjective, it stands to reason that not all people are going to agree on what “good” is, so I’m in no way saying that my opinions are the “good” way or the only way. This is just how I do things and why.
This YouTube video shows in (probably too much) detail how I am set up to profile these days. It has changed over the years as I profiled amps in different locations and with different mics (fathead, royer, etc.) and different mixers. The recurring theme is the mic placement of the 57 and ribbon mic very close together. Here are 20 minutes of your life you may not get back, but perhaps get something useful out of them:
I think the differences between the straight Kemper profile and the real amp are almost inconsequential. The fact that the Kemper is able to further tweak parameters like definition, tube shape, compression, and clarity makes it even more powerful at times.