I’m in a similar situation to you... I have floor standers (that don’t even go as deep as yours) and two JL 12" subs, in a system that does double duty for HT and 2-Channel. I found an amp I really love, but it’s an integrated, and I had been banging my head over how to integrate the subs.
While I was also expecting the mains to get better, with the subs taking over bass, I haven’t noticed any difference. So I think your intuition to move on and obsess over a different aspect of your system is wise :) Where two 12" subs will make a difference, is providing deep prodigious tight bass, which is amazing if you watch movies or listen to certain types of music. So, if that’s what you’re craving, the extra trouble to properly integrate subs can be worth it--but if all you’re wanting is to improve the performance of your main speakers, I think you’ll be disappointed.
While I was also expecting the mains to get better, with the subs taking over bass, I haven’t noticed any difference. So I think your intuition to move on and obsess over a different aspect of your system is wise :) Where two 12" subs will make a difference, is providing deep prodigious tight bass, which is amazing if you watch movies or listen to certain types of music. So, if that’s what you’re craving, the extra trouble to properly integrate subs can be worth it--but if all you’re wanting is to improve the performance of your main speakers, I think you’ll be disappointed.