The Joseph speakers have an incredible clarity give a nice insciveness to the higher frequencies. However, as you move up from the lower mids, the sound does lose a bit more body, so things like upper female voices, then wood blocks, drum cymbals, will tend to be rendered thinner and dynamically a bit laid back.
In general I agree with your assessment, but as usual, caveats abound. I think some of the shortcomings you mention have to do with amplification. Earlier I was using a tube amp with my Perspective2 speakers and did notice some thinness in the mids. But once I moved to a more powerful amp (Aavik U-280), this problem ceased to exist. The sound I get now is full and tonally rich across all frequency ranges.
Also, after hearing the JA Pearls twice -- the second time was a very long session, the differences between Perspectives and Pearls are quite significant in my opinion. So yes, it retains the strengths of the Perspectives, but boy does it add scale, heft, and a sense of realism that is breathtaking. It just pressurizes the room in a way that Perspectives simply cannot. The Pearls are one of the best speakers I’ve heard cost no object.