Do we really need anything more than 8" woofer and 1" tweeter for medium size room?

Erik, let's assume that room acoustics and wall current are done right.
I would say that my 8"/1" with 120 watts/ch Redgum integrated amp go down to low 30s in a pretty good fashion. Vifa drivers. But that's still only $1.5k speakers with $1.7k integrated. I can imagine that the same speakers would do much better in every respect with, say, class A Gryphon or older Rowland or Lamm hybrid, and many others. Not to mention better speakers with better drivers.

The speakers cost $1.5k 17 years ago, and the amp cost $1.7k 16 years ago.

Inna, I agree that all things being equal, 8" would be much better for bass but my room constraints would just exacerbate those room nodes. I've learned my lesson from having too big a speaker. Again, ask my neighbors. :-)

As to a single driver, I'm with you on this. I used to have a pair of Hornshoppe Horns which satisfied me for quite awhile but that 4" single driver just couldn't plumb the nether regions to my satisfaction. That, and the lack of "meat on the bones."

I just feel that since all speakers are a compromise, one should get one that gets the highs, mids and upper bass as close to perfect as possible within the confines of one's space: just let the room fill in the lower end as best as possible unless you're fortunate enough to have a room large enough to use a good subwoofer.

All the best,
Nonoise

I have AZ Adagois ...two 6" transmission line .they sound killer.fantastic  speaker for the bucks ..mine are on 1.5" audiopoints( starsound)
I must confess i do have a sub it gets some use ,but not all the time 30hz down ..

Assuming here the OP is referring mainly about stand mount speakers, here is my take.

I have a pair of Klipsch RB-75’s that have 8" woofers and 1.75" compression drivers(titanium) with 8" horns and boy do they play bigger than they have the right to. Strong tight punchy bass, clear articulate midrange, and detailed but not strident treble. Dynamics would be an understatement. They are essentially floorstanders with "bookshelf" cabinets(20.2" x 10" x 11.8", 32lbs). I have owned other bookshelf speakers with 8" woofers but with 1" tweeters and none have the presence, smoothness, and dynamics that the 75’s have. I have the RB-75’s paired with a Klipsch RSW-10d subwoofer in a 4000ft3+ room and the combo has no problem filling the space with some ear punishing dB’s.

With all that said, I do think a well designed 6.5"W/1"T speaker with a smallish sub can hold it’s own in a small/mid sized room with decent dynamics.

Bill