Smaller room usually means smaller speakers possible for good bass.
Also listening position is often closer to speakers than otherwise. Often the closer drivers are perceived to be a point source from the perspective of your listening position, the better for soundstage, imaging and coherency top to bottom. Avoid speakers with large physical separation between drivers.
Lots of good affordable monitor and affordable smaller floorstanding speakers in the $2000 or less price range to work with given these two criteria to help choose.
I would try without a sub initially, and only add sub or subs later if desired, making sure sub levels can be integrated cleanly as needed.
Also pay attention to different amps that might be used to best effect depending on the speakers. Smaller less efficient speakers with good bass capability often need a surprising amount of power to deliver optimal results, often 150 w/ch or more. Larger higher efficiency speakers for a room that size, like Klipsch Heresy for example, can get away with much less power and may even sound best with a lower powered tube amp. That is assuming you listen to a variety of music genres and may want to go to lifelike volumes when called for. Using a powered sub even with less efficient speakers will offload work from the mains and enable better results with a lower power amp perhaps there.
