Single driver speakers without the pitfalls?

In researching SET amps, I have learned a lot more about the sort of high efficiency speakers that they are typically paired with, including single driver models like Omega, Blumenstein, Teresonic, etc.
The advantages of these designs are well acknowledged: coherence, imaging, high-efficiency and so forth.
At the same time, there seem to be equally well acknowledged drawbacks to these designs: Limited bass response, rolled off highs, and a harshness or "shout" in the upper midrange.
Some designers, like Tekton and Zu, seem to take the approach of getting the best of all worlds by joining a wide range driver to a tweeter of some sort. (To some extent, my Reference 3AM De Capo monitors take this approach.)
What I'm curious to learn is whether you think there are any single driver, full range systems that transcend the above limitations.
Eager to hear your thoughts.