Am I missing out on a lot if I’m just using the 10 inch subs I have in my DM70 towers?

This might be taboo to a lot of you, but I just moved to a house so i have more freedom with volume. I have 2 DM70 towers, a DM center channel to match, and 2 surrounds (KEF Q150 pair). Sounds great, the subs in the towers handle anything i need, but i’m wondering how much I’m missing out by not having a dedicated subwoofer. I wanted to add atmos channels, but my receiver is only x1700h, so 7.2 which means i’d need to upgrade to a 9 channel at least.

So naturally I looked into a proper sub next, but doing this while listening to music with the subs in the DMs going, it sounds pretty good to my untrained ears.

Would it really make it THAT much better adding a proper sub like a PB1000 or SB2000? (similar price points, i know they’re naturally different)