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

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

I got floorstanding speakers, use Polycrystal spikes and Boston Audio graphite tuneblocks for speakers under the spikes. Wooden floor.

The stand mount adagios jr. are two 6" and they are amazing! imho. i have the floorstanders and love em..I couldnt imagine a 10-12" woofer in any speaker for me anymore .i had ADS  something 15" yrs ago with 2 10" they were ok for the times.Bring the low end if needed with a single or two good subs.(Although i am oftem perplexed on this forum why people rave over very "inexpensive subs but yet spend 10k plus on spkrs).. good subs make the difference to me within reason for your setup of course.And a good 10"  or two 8" tucked away properly will bring that bottom in fo' sho' ...I feel like an ad for room treatment but that is one of the bigest changes in my sound i have ever made in low end 

Willand, I like your description of "they are essentially floor standers with bookshelf cabinets". That closely approximates how I feel with my Clearwave Duet 6 monitors.

All the best,
Nonoise