I think Al has given you great advice. Get the room correction eq and a stereo pair of subs. You will be happy. Regardless of how new your amp is I can't see it going from weak bass to deep bass. Gains made during break in are usually more within the margins and not life altering. What you are missing is most likely due to room and speaker limitation.
The only thing I would do differently is try the eq before buying the subs. It may bring the level of sonic satisfaction you desire. However, in the end, you can't go wrong with great subs
The only thing I would do differently is try the eq before buying the subs. It may bring the level of sonic satisfaction you desire. However, in the end, you can't go wrong with great subs