Whenever I hear "subwoofer", I immediately think home theater, and your speakers are too small to adequately produce convincing bass. Your music preferences are all types that tend to focus on midrange as well, so I'd have to say it is time to put your foot down and man up with a decent pair of three ways. That being said, it is sometimes necessary to condescend to the wishes of significant others. I have a personal space for my music listening, so indulge in my favorite 3way speakers. Lots of modern multi-driver speakers will certainly play loud, but will never produce the distinct layers of treble, mid-range and bass that classic style three way speakers can. It is hard to escape the distinctive boom boom of a subwoofer in the background somewhere, distinct from the other ranges. And as mentioned by others....never take anyone else's suggestion as your choice until you've actually listened to them yourself. Your setup is totally unique to your space and your ears are different than others as well.....it is critical that you serve yourself here.......
Much of this post is so full of incorrect BS I'm not sure where to begin.
My recently retired Acoustat Spectra 22's (purchased new in 1989) came with their own subwoofer. This was way before HT became popular. The truth is, a decent subwoofer(s) properly integrated will improve the sound of even the best 3 way 12" woofered "vintage" speakers.
For 20+ years I've been using a pair of DIY 12" TL subs (Pass El-Pipe-O's) that are currently crossed over at ~50Hz and equalized flat to ~18Hz. Those subwoofers are currently enhancing the bass of my Magnepan 1.7's (with the Acoustats I used an 80Hz crossover frequency). Other than being a large visual presence in my dedicated acoustically treated room, the only time anyone audibly knows they are there is when I turn their amplifiers off. The lack of deep bass is instantly and easily audible to anyone. The two biggest problems with many subwoofer setups are.
1. It's a cheap HT oriented sub that came with an inexpensive HT in a box. This usually means it doesn't have any deep bass.
2. It's set up with a crossover point to high and most often turned up to loud.
Any "decent" properly adjusted sub woofer will only announce it's presence by the lack of deep bass when it's turned off. If you can tell there is a sub present it's almost always too loud.
The speakers that won't benefit from a properly adjusted subwoofer tend to be all out assaults on the state of the art and most of them include their own subwoofers. In 50 years with this hobby I've never heard any 3 way 12" woofered speaker that wouldn't benefit from the addition of one or preferably multiple subwoofers.
For those who are curious there are a number of threads on Audio Karma that discuss this very subject. The general consensus is that subwoofers improve the low end with the only drawbacks being the cost and the space required. The only question is, distributed (multiple mono) or stereo subs. I use mine in stereo. But then, I also use a separate electronic crossover.
BTW: I use a calibrated microphone, REW (Room Equalization Wizard) and a parametric DSP to equalize my system to be flat to ~18Hz at 85dB at my listening position. REW is available as a free download from the REW web site. Mini DSP has the Umik1 calibrated microphone for $75. Parts Express carries the same mic for a slightly higher price. Both microphones come with an individual calibration curve that can be plugged into REW.If you can "hear" a subwoofer it's turned up too loud.