You asked a complicated question for me. I absolutely loved my Electra 926's for a long time after I bought them. My wife did too, which was very important at that critical point of my audio adventure. I still like them a lot overall and consider them a must to audition in their price range. But, I would offer a couple of caveats that may or may not be relevant to you.
First, they are a bit light on bass in big rooms/ open spaces. My room is not too much bigger than yours (24 x 18), but I have a ceiling that is around 16 feet at its highest, and the bass is definitely a tad on weak side. I have yet to try a Rel sub with them, though plan to in the near future to see what that does for the problem. It may end up making a huge difference.
But a larger issue for me now is that these speakers have a distinct personality and sound. In that respect they are very much like the Sonus Faber line, such as the Cremonas. They do some things exceptionally well, even magically (vocals, jazz)but others less well (rock), though not necessarily poorly. But I have begun to notice that they are influencing the music I listen to, pushing me towards what they do well. That is not a good thing in my judgment.
But this complaint is really just a reflection of my changing tastes and preferences as I develop a sense of what I personally want out of audio. I have no guarantee that if I switch to another speaker that I wont end up coming back to the Electra 926. They really are special in many respects.
Regarding the 907BE I actually did NOT like these very much at all. I found them too bright, at least when paired with the equipment they were demod with.. The 926s are a completely different speaker to my ear, and greatly superior. New, they are out of your price range, but used they can be had for around 2K or so. In fact if you live anywhere near Michigan, I might have a pair for sale sometime in the future. : )