Pondering a change after 30 odd years...

Musicfan, Way back I had a pair of Acoustat Monitor fours that I mounted on top of RHLabs Subwoofers!! I loved those subwoofers. Never should have sold them. Mine were walnut.
Anyway check out my system. I currently run 2+2's which I have owned on and off for 40 years.
Unless you take an ice pick to the panels they will last forever. So, don't worry about that.
The only real downside to these speakers is that they are very selfish. You have to be seated in exactly the right spot or the high end disappears. I an going to move to Sound Labs 845's just because of this problem. The Sound Labs are also an easier load and a bit more efficient.
You have been living with the 1+1's for a long time. Switching to any other type of speaker is liable to be a disappointment in the long run. You might tolerate Magnepan 3.7i's but once an ESL fan? It is hard to lose the inner detail, transient snap and sense of the third dimension that no other speaker has. Most people think all ESLs are like Quads and have never listened to a sturdy line source ESL like yours. Your soundstage is way more lifelike than what you get out of any dynamic loudspeaker except perhaps the ones that are set up as line sources (Pipe Dreams).
Getting a speaker better than the 1+1s is not going to be easy or cheap.
The least expensive would be the Maggie 3.7i's. I would audition them for at least several hours. There is Sander's Sound Systems model 10 but I actually think your 1+1's are better! Sound Labs makes the only serious contender but the 845 is a MONSTER. However, Sound Labs will do custom speakers. The 545 is 24 inches wide. (845 is 40"!) I bet they would make an 8 foot version for you. You are use to a full range line source. Decreasing the height of the speaker will dramatically reduce the size of your image. If you like that presentation (I personally will never give it up) you best stick with an 8 foot speaker. Anyway, An 8 foot 545 would be just four inches wider than my 2+2's, a very nice size with good proportions. 

My Apogee Slant 6's many years ago blew the ribbons, so I got to explore a lot of speakers in the intervening years.  My experience/bias meant I hunted speed, imagery and the sound wall of the ribbons.  I evolved to a pair of Dynaudio C2 Plats, which unfortunately didn't sit well with my original amps so after a number of combinations I eventually found my end combo with a Supratek DHT pre (adds the warmth and some color), Accuphase A70 (just clean power).  So matching new speakers with your existing amps could be a journey.  I also run a C22/Mc75's system but too much color with the Dynaudio's so use different speakers with them.

I recently had my Apogee Slant 6's fully restored, new ribbons and rebuilt bass speakers and fell immediately in luv' with them again, now being driven by an Ayon pre and Radford STA-25, and never sounded better.  I also picked up a pair of Apogee Slant 8's cheaply and not much between them and the Dynaudios (a bit more dynamic), I rotate them every couple of months.  So my 30 year old speakers compete very well with my modern speakers.  Maybe hold onto your Acoustat 1+1's, you never know how you might feel in a few years.

So sometimes what you have and luv' are for a reason, but then again its the journey that's fun, but can be frustrating as well.   Enjoy your search.

Another for Tannoy (and I am a very happy SonusFaber user)

I've heard but never had the 1+1 but did own 2+2 with medallion transformers driven by both Threshold SA4e and Krell KSA100S.  Source was a Theta Miles directly into the amp.  The system did a lot of things right and was able to pull out a lot of inner detail due to the huge radiating area.  Imaging was not a strong suit.  Yes, the Acoustats threw up a huge soundstage, and that was great for some music (Tangerine Dream in particular) but sounded overblown and ridiculous with other fare.  I moved on as audiophiles are apt to do and have been through numerous speakers.  I have a pair of custom/DIY loudspeakers that have the same appearance as the Legacy Focus with Eton drivers.  Standing a little over 5' tall, they put up large soundstage, actually they fill the room with sound and completely disappear.  In the dark or with eyes closed, I really can't tell where the speakers are.  Images are properly sized, dynamics can be fantastic depending on source/amp/cables.  Again, these aren't actual Legacy Focus and may be better with the Eton drivers but it may be worth the effort to hear real Legacy Focus loudspeakers.  They are quite efficient so you'll have plenty of power on tap and you won't need subs.  

"Is this love or confusion" Jimi

Its not often that folks actually read the posters question before making their well intended speaker suggestions. I'm not a panel fan at all but I'd say you're getting a few good beginnings to look into.

Have fun with it, welcome back, and keep your subs.