Welcome!
The basis of my system is simpler than yours: NAD M10 "streaming amplifier" and commissioned transmission line floor standing single driver speakers in a well insulated 8ft x 13ft x 21ft room with a midfield setup. Saved most of my library as Tidal favorites and the rest to a flash drive that plugs into the M10. But the devil in the details. Also have 3 carefully placed subs, 10 GIK absorption panels (find them here at Audio Circle), 3 tall bookcases serving as casual diffusers, and "Late Ceiling Splash" tweeters (see Audio Kinesis in the sponsor child circles here at Audio Circle).
Single driver speakers provide coherence and imaging like nothing else, but they have their limits. There is no such thing as a full range single driver speaker. Typical high efficiency single drivers have colorations, many have limited output. Even my speakers that use discontinued but well respected Fostex F200a drivers competently cover only about 6 octaves (rated to cover 9+ octaves) thus the subs and tweeters. The subs/panels also address inevitable in-room bass peaks/dips (suggest reading Floyd Toole's "Sound Reproduction").
A highly viable option to single driver speakers are active monitors. (Single driver designs by definition are active.) By active I mean use of a low voltage crossover that fees one channel of amplification per driver. Actives come in many forms, but the crossovers being low voltage can be much more sophisticated than found in passive speakers. Actives can be pure analog, pure digital (often wireless), or combinations thereof. Actives are undeniably superior in terms of design, cost, and sonics. Lets the amps "see" the driver load to better react. Saves the cost of amp cabinets and speaker cables. And provides greatly improved dynamics, flatter frequency response, improved imaging, and gobsmackingly deep/full bass for the given driver/cabinet size. Actives are used by 99% of studios that record, mix, and master the music you listen to.
