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
Have a look at the Zu "Dirty Weekend" offer.
Great full range speakers that you can borrow for a weekend.
Not huge, very efficient and sound wonderful
Wife may not like the looks... but golden ear triton 1 is at the top of you budget but definitely a full range speaker and the woofers are powered, so your 70 watts is only driving mid and hi... I have the GE references driven by a carver 275 in a large room with no problem...
If your top end is $5k, make a list of full-range speakers that retail for around $8-10k, then sit back and wait for demos or used.  It will happen.
I haven't listened to a lot of speakers but I would say the the Vandersteen CT Treo was the most dynamic I have heard.  Out of your price range new but maybe used would be close.  Also only comes up to your waist or a little higher depending on how tall you are.  I have the same requirements from the wife, "Don't overwhelm everything else in the room". 
I suggest looking at the AudioKinesis Swarm Subwoofer System, which is not expensive for what you get. It is much easier to find speakers that sound great from about 50Hz and up but getting those lower octaves to sound right from your main speakers can really cost some money. There are benefits to multiple subs that you just can't get by using only your two main speakers. If you decide to upgrade your main speakers later, the Swarm will likely keep pace and do a great job filling in the lower octaves.

^^This. Or for super high value you could DIY your own DBA with one Dayton SA1000 and four 10" subs for about $2k leaving $3k for some nice small speakers, that will give you awesome imaging with awesome bass. The DBA helps with spouse approval because they are not fussy with placement and can go in corners or behind furniture.