Two surprising things I found that improved my imaging and staging...

+1 sns and baylinor

baylinor hit the spot. And I'll second the recommendation of Jim Smith's book. In any case, it is certainly true that room acoustics are too often an overlooked element in one's system, every bit as important as any component—and "free" to experiment with. Of course, unless your listening room was purpose-built, there will be compromises, the notorious WAF being one (hence, not completely "free").

I have a pair of Scientific Fidelity Tesla speakers that I love, even against half a dozen high-end replacements I've auditioned in my listening space over the years and decades. You've never heard of these, probably, because Corey Greenberg gave them a bad review in Stereophile when they came out, and Mike Maloney's new audio company never recovered. But, at least in my space, they handily out-perform speakers Stereophile and other magazines awarded various accolades to, and which cost orders of magnitude more.

Mr. Maloney recommended toeing in his Teslas, and I've found they sound best toed in even more, to the point that their trajectories meet about two feet IN FRONT of my face. Their one deficit is that they tend to be a bit bright in the upper midrange, and this is tamed somewhat by having them off-axis. Also, extreme toe-in improves imaging for listeners sitting to the immediate left or right of the sweet spot, since that set-up has the more distant speaker facing the off-center listener straight on. Finally, this configuration is surely made optimal by my unusual room: very high trapezoidal ceiling, with the speakers sitting at the left and right of a large stone arch that opens into the entrance foyer of the house, so there is no wall behind them (although there are side walls, from which the speakers are several feet distant). Imaging with this configuration is simply astonishing. I can "watch" particular instruments (with eyes closed!), which makes it easier to follow individual lines of counterpoint. The clarinet is clearly sitting to the left or right of the oboe, and the horns are clearly further back. Such imaging is much more vivid than it would be at a live concert, and yet feels in no way "enhanced" or unnatural.

“And don't have any equipment on high racks between speakers. Not having anything other than room treatments between speakers is perhaps the most important thing in getting 3d imaging. You can have equipment low to ground, anything higher than 20" or so starts affecting my sound stage.”

This post pertain to using a 5 channel HT system for 2 channel listening. 
1. Should I put sound absorption on the left and right of my center channel speaker*/amp stand?*top of same between 36 & 38” from the floor. 

2. Pull out my 42” high LR towers a few inches so my center front baffle is several inches behind the LR front baffles? Towers’ tweeters’ measure center to center  ~11’. I could also push back the center speaker 2-4”. 

All this from system that costs less than $500 and no ac treatments or room treatments?

No you are wrong here...

My room is treated completely with passive reflective diffusive and absorbing surfaces...

Not only that but my room is actively controlled by a grid of more than 40 tuned Helmoltlz resonators and diffusers ... I call that a "mechanical equalizer" created after Helmoltz method and many over devices ( a Schuman generators grid and a ionizers grid etc) i will not spoke about here all of my creations homemade.... I dont bought tweaks , i create mine...


My motto is:

Dont upgrade BEFORE embedding mechanically against vibration and electrically decreasiing the HOUSE noise floor, and especially never before working passively with acoustic material surfaces and actively with Helmholtz mechanical devices control your room...

I can only say this, and I’m not being facitious, I’m rather envious of you. Perhaps, my obsession and others, with reaching for highest sound quality has all been a waste of time. Just as with the phantom center image, it’s all delusion anyway. If I had the perceptive powers you have I needn’t have spent all this money and obsessed over every single detail in this needless pursuit.

You could be envious in a way,   because even if  my low cost well chosen system is not the best ever, most people here own better system than mine but they are not well embedded and especially put on non treated and non controlled room acoustically, my system though is one of the best possible for his PRICE/S.Q. ratio....

This is the reason why i smile at the idea to upgrade my system ...

I already calculated the cost for a true upgrade from my system of 500 bucks : 15,000 us dollars at least and perhaps more for example from my Sansui AU 7700 to a Berning ZOTL 40 amplifier...

But this upgrade even if it will be a real one is not so much appealing because of what i really already have for the price of peanuts...

Audiophile experience is mainly acoustic for at least the bigger half part.... 😁😊

Marketing is not science.... Acoustic is a science...

Staying away from toe-in might be minimizing cross wall first reflections while maintaining same side wall reflections, which are now reduced in volume and slightly more delayed by having the speakers further from the wall, thereby minimizing or perhaps even optimizing comb filtering effects. Same side wall reflections tend to widen the soundstage. Cross wall first reflections can be a mixed bag, often not helping with imaging but under the right circumstances might help with spaciousness without harming the imaging. In your smaller space they probably aren’t helpful. Having the speakers closer together helps to solidify the center image.