Look up "Hoffman's Iron Law". Bass performance is compromise between size, efficiency, and and extension. You can only pick two. You can't get all 3.
Power is cheap relative to the old days so the usual solution is to go smaller and less efficient. Of course if you are running low power tube amps (like the old days) going big is your best option. Given that 5-8 cubic foot monkey coffins (see Cerwin-Vega D-9) are out of style, the usual solution is to go with a small, inefficient, high-powered subwoofer and pair it with a reasonably sized high-efficiency mains crossed over at somewhere between 50 and 100 Hz. Ultimately it comes down to how much space you have and how you spread the $ between amps, drivers, and cabinets.