Hey my friend,
I can see in your case why a subwoofer is a good idea. I wrote an article which includes information on how to get great results from a sub. I will say this: It takes work. The integration with the speaker and the room are not straightforward.
https://speakermakersjourney.blogspot.com/2020/04/how-to-not-buy-subwoofer.html
From my experience, it's not that panels and dynamics have speed issues. It is that panels couple to the room a lot easier than dynamics. Properly set up, a single sub woofer is just as "fast" and transparent as any panel.
I can see in your case why a subwoofer is a good idea. I wrote an article which includes information on how to get great results from a sub. I will say this: It takes work. The integration with the speaker and the room are not straightforward.
https://speakermakersjourney.blogspot.com/2020/04/how-to-not-buy-subwoofer.html
From my experience, it's not that panels and dynamics have speed issues. It is that panels couple to the room a lot easier than dynamics. Properly set up, a single sub woofer is just as "fast" and transparent as any panel.