Thanks for the link, I'm looking forward to give it a try.For consumer-oriented solutions, amongst others, I have in-depth experience with Mini, which relates to ...
"(B) Same with the 10kHz trough, which is told to be a must btw, and the 14kHz something peak, again a must."
Do you have hard evidence in general for that, or in particular in an IEM?
On the question, there are personal HRTFs for diffuse field, and I've seen those dips and peaks all the time. B&K published a paper on the acoustic impedance of the ear canal which shows the resonances clearly. Hence they must be seen in measurements of an IEM put onto the canal.