Appreciate the suggestions everyone. Very helpful! Below is the course of action that I am in the midst of carrying out based on the suggestions.
As I had removed most of my furniture from my living room to address this issue, I decided to get on my knees and do the subwoofer crawl (thanks @fstein ). I found the locations that I thought the bass sounded mildest (I am rather bass shy), and for now, have placed them on the right of the front wall (behind the speakers) and immediately behind my sitting position, against the back wall (thanks @avanti1960 , @tablejockey , @12many ).
Over the next couple of weeks, I will make minor adjustments to the location and gain of the subwoofers, in order to see what works best. Also, having done the subwoofer crawl, I now know the locations in my living room where the bass is most boomy and will try using bass traps to see what effect it has on the sound of my system (thanks @rick_n ). If all else fails, I will try the DSPeaker 8033 II as suggested by @kota1 .
Thanks everyone for the helpful suggestions!