I really like full-range speakers with lightweight and additional whizzer cones, but they lack the deep bass we are used to from “standard” speakers. There are back loaded horn designs that improve the bass somewhat, but they usually cause other problems. I have been working on this topic for almost 50 years and have tried and listened to many drivers and designs.
In the end, I developed a completely different approach. A: The driver must have an electromagnet and B: There must also be a large diaphragm for the low frequencies. Perhaps the effort involved is too great for some, but listening to music with the Wolf von Langa London really gets under your skin and gives you boundless pleasure! At least take a look at the speaker; in the US, Colin King (Gestalt.Audio) may be able to arrange for you to listen to it. https://fieldcoilloudspeakers.com