Small Floorstander?

The Proac DT8 are excellent also the Proac D20 .This are wonderful small standfloor speakers which can work fine on small space without the bass becoming overhang .

I've owned a pair for over a year now the ProAc DT8's would meet your requirements. 

I owned a pair of Preludes for years and they're a GREAT speaker (unique to the Silverline speaker line in that they use magnesium/aluminum drivers, unlike the "plus" version)...only sold them as I wanted a very high efficiency speaker to use with a relatively low output single ended amp...I did use this amp with the Preludes for a while though and it sounded tremendous within the amp's limits with them. I hated to sell 'em, but if I don't use things I like to pass them on. Alan Yun told me when I bought them that they sound more coherent single wired and he was absolutely correct. 

Although I have only heard the Preludes, either the Silverline Audio Prelude or the Prelude+ would be worth n audition.  Thin and lite (under 35 lbs. each), they produce a surprising amount of bass, and have a wonderfully wide sound stage.

@dhcod  +1 on the Gallos if you can find a used pair for sale. I picked up a gently used pair of 3.1s several months ago for just under 1K and couldn't be happier. And because I was under budget I was able to upgrade my interconnects too :-) 

I have a similar room size as you and found the Gallos to fill it quite nicely. They're very lively, dynamic speakers that I'd say fall on the just warm side. They definitely are not bass shy and with the option to add a sub amp to the secondary coils you an always add more if you find it lacking, but that hasn't yet been a problem for me and I listen to a fair amount of hip hop. 

A lot of great ideas! I’ve got listening sessions scheduled for this and next weekend. Thanks!

Totem used to have small speakers with great  sound. Their newest are really thin. 

Tekton OB Sigma's. I run mine with a sub & they are wonderful speakers. If I had a room your size, I'd add another sub. These throw a huge stage (width & depth) with realistic sized musicians within. 

Save your money and just buy a pair of wharfedale diamond 230’s...great.
Hifi choice, hifi News, and what hifi agree, with 5 star ratings. Warm sounding, huge soundstage, plenty of detail, and with the down firing port similar to the tannoy but much cheaper, and you can place them closer to the rear wall without negative consequence. It’s a 2.5 way speaker and you can bi wire it as well. I mean 5k for speakers, wow...no need to spend that much with all that’s available at reasonable prices. These speakers kick ass of those twice or more the price. Usable down to about 37 hz -3db....just $598 for the pair at music direct, on sale...crazy. The bookshelf version of this speaker, the diamond 225, won the stereophile budget product of the year in I think 2017. The 230 adds more volume, plus an extra bass driver, yet uses the very same tweeter and woofer as the 225.

“For the money, you’re getting a real deal.”
– What Hi-Fi?, five-star review

"...It presents the soundstage in a clear and upfront manner. Because the three drive units integrate so well, it sounds very sophisticated considering the price."
– Hi-Fi Choice, five-star review

"Smooth, open and detailed, yet powerful and confident, it transcends its apparent limitations to deliver excellent results. Factor in attractive styling and fine build, and what’s not to like about this little gem?"
– Hi-Fi News, Highly Commended review

Tekton Lore

+1 For Spendor. Own the A4s, small and easy to move, great punch in the low end.  Warm mids, and just flat out beautiful sounding.

I'll 1+ the Heresy. Great little loudspeaker.

ProAc D30RS/D20RS or the Spendor D7 should meet your requirements.

They might be a little heavy for your requirements and they are certainly unique looking (some hate the ultra modern spaceship look) but a pair of used Gallo 3.1's or 3.5's. I think they weigh in at about 55-65lbs, but are small and I have little problems moving them in and out of listening position. 

Klipsch Heresy IIIs...they make up for their low height by being tilted up on supplied little bases, and are absolutely world class sounding little gems. Add a sub and they're even better.

Immediately thought of Maggies though you'll probably want a sub with them.  Fortunately the sub isn't so placement-specific and doesn't usually need to be moved for listening sessions.

I have D7s and I although they are small relative to many floorstanders I don't consider them easily portable and readily shuffled in and out of a listening area.  They are 38 inches tall and weigh close to 50 lbs each.

A pair of Daedalus Athena V2's just came on--grab them. They even come with wheeled platforms so you can move them around. Sound is exactly what you are looking for and they are in your price range.

Totem Arro, Hawk, Forrest and Sky will all meet your needs at different price points.

+1 for Spendor A-7. Two months in and sounding better every session. 

ProAc have some manageable sized floorstanders that should give you plenty of bass in that room

Spendor A7 new for your price (40lbs for moving) or Spendor D7 used (46lbs). Both well reviewed.  

Check out the Spendor A line!
https://www.spendoraudio.com/

Bryston A 3
20 years warranty
https://hometheaterhifi.com/reviews/speaker/floor-standing/bryston-model-a3-floor-standing-speaker-r...

Tannoy Revolution XT 6f
http://www.hifi-review.net/465-tannoy-revolution-xt-6f.html

Vandersteen 1ci's come to mind.
Unfortunately, a small/light speaker will always be a bit on the 'bass shy' side as it is more a part of physics.
Bob