Hi Lon,
Good question ..... ???
First, I must shamefully admit that I have not yet tried Dank's suggestion of flipping the cabinets around and firing them into the corners. As much lip service as I (and many others) pay to the concept of "it's only about the sound", I don't think I could look at the backs of the cabinets knowing how nice the front looks .....

Even so, I will still have to try it in the near future.
Concerning the different amplifier setups, I am torn between running all speakers from the Select and powering the Imperials from the plate amp. The plate amp will produce more "grunt" ..... hands down. Most of the folks who have visited me for a listening session are very impressed with the output from the Imperials with 100 watts pushing them ..... but being impressed and enjoying music on a daily basis are two different things, as you well know.
As you might imagine, it's a totally different effect running the Imperials full range from the Select. When you drive the Imperials with the plate amp, it's not feasible to run them full range because it muddies up the lower midrange ..... at least in my experience. So ..... a crossover point has to be chosen on the plate amp to get a good blend between the main speakers and the Imperials. I'm still playing with it, but somewhere between 50 and 70 hz seems to be a good point.
Another issue that I have run into is that my room has a "bass suckout" at the spot where my listening seat normally sits. If I move around the room, some areas have a lot of bass energy but the normal listening position has nowhere near as much bass. So, I have been moving my listening seat forward and backward and experimenting with the toe in of the main speakers to make it work. I'm getting there .....

I'm convinced that there is something positive to the full range parallel stereo setup ..... but the benefits are more obvious with some recordings than others. As several people have mentioned that have heard the Imperials, the bass is only one aspect of the overall sound ..... the other is the ambience and sense of the recording space that is added. In my experience, running the Imperials full range in parallel with the main speakers produces this effect to a greater degree.
My very best wishes to you and your wife,
Randy