Really need some help finding a full range speaker


I've thus far been on the sidelines here, but I must say I've been very impressed with the knowledge many of you bring to this forum . I'm hoping to tap that knowledge, if I may, and get some help finding a new pair of speakers.

I currently have a pair of Paradigm 75f's and I've been very happy with them. To me they sound neutral, fairly accurate and exciting to listen to. But with just a pair of 5.5" drivers providing bass, they are lacking seriously at the low end.

I"m driving my Paradigms with a CJ LP70S which puts out 70 watts per channel. It has no trouble driving the 75fs but I'm inclined to buy a more efficient speaker this time around. I"m also very interested in maintaining or even improving on the accuracy and neutrality I"ve been enjoying with the Paradigms.

I'm searching in the used market and looking for a pretty significant upgrade. I'm very open to vintage options and am searching in a fairly wide price range from $1500ish (used) up to around $5k. I'm concerned about not having the opportunity to demo the speaker before I buy it, but am highly motivated by the cost to value ratio available with used speakers.

One final concern is size and aesthetics. My wife is simply not going to tolerate a tower speaker bigger than she is (or I am for that matter) and more flamboyant designs are not welcome in the listening room that doubles as my living room. I'm hoping to find a fairly straightforward looking speaker that's large enough to accommodate bigger drivers but doesn't completely overwhelm the room with their size.
thebrokenrecord
I will add a third recommendation to look at the Audiokinesis Swarm subs; with them you will get good bass to 20Hz.
The speaker you need to do 60Hz or so and up is then a fairly easy prospect as it does not need to be large!
+1 ianrodger.
ZU:  I purchased ZU Omen Mk II,  3 months ago. I’m waiting for new Soul Supremes to arrive now at end of month. I do use a subwoofer They have an excellent trade in program. Check out the details on their website.  I got full purchase price back for an upgrade to the Supremes. Their speakers are fantastic or I wouldn’t be trading up. 
Bent
Three brands to consider:
Vandersteen, as mentioned above.
ProAc - work beautifully with CJ tubes. 

Monitor Audio - Gold 200 or 300.  I have GX300s that I got for ~$1600; if you can find a 4th or 5th gen set of Gold 300's I'd do that - and they'll be in your price range.
Good luck - and enjoy!
adam8179 - Where did you buy your bass traps? I like that suggestion a lot and adding room treatments is another item on the audio "to do" list.

Regarding the bass on the 75f. I've actually been impressed with how much bass they deliver give the size of the drivers, but I had the misfortune of hearing the Wilson Alexia at a friend's house, playing a record I brought and knew well. I was floored at how much music was there in the lower frequencies that I didn't even know was there. Granted, it's a totally unfair comparison, but eye opening none the less.

I really like the way the 75f's do drums and bass, but I sometimes find it hard to hear a clear difference between the two and understood this as a function of the speaker limits in low frequency extension.

Thanks!