Front baffle size for open baffle Audio Nirvana 15" Ferrite

I've built the recommended open baffle plan for the Audio Nirvana 15 inch drivers some 15 years ago. It was a rough cut, with shop wood etc. I liked it so much I've kept them, partially in fear that I might not like something if I changed it, since they suited me so perfect. The front baffle is 24" wide and 30 inch tall, and leans back with a gently slope. I use a Aperion dipole AMT supertweeter which cuts in at 16Khz as well, and I use digital speaker EQ to increase bass below 80hz. This year I replaced the old drivers with the new 15" ferrite, it was a nice upgrade.

I am going to finally build a furniture grade replacement, and I am thinking of moving the driver up about 4 inches to closer to ear level. I've also read about changing the width of the front baffle. Right now there is 4 inches of baffle on either side of the driver. What is the effect of narrowing or widening the baffle? Would it be a good idea? I've heard narrowing it might improve soundstage.

I've also thought of tapering the width of the front baffle a bit (so it is a truncated pyramid) with 24 inches on the bottom, and narrowing it so it it just covers the width of driver and continuing that to the top. My theory is it may look cooler, and less right angles is probably better for the sound.

I have also been looking at what material would be the best, I'd sure like to get something denser than the plywood I have. Panzerholz would be perfect, but probably no chance or affordability of that here in the USA anyway. Other ideas??
How about adding a side-wings to existing baffle for experiment?
Make them unsymetric width, say 8in on one, 12in on other side. Use piano hinges to connect them so you can change the backward angle. Than see if you can get some improvement.
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In my case I didn’t experiment much with side wings but but I think it’s a good direction. I used an open back box instead of only a front baffle. I have found it to be a good solution for me. The driver is at ear height and I use no tweeter with it. Bass goes deep enough for me without EQ.

Of course, it is not the same bass I would get from my commercial floor standing closed box speakers and I don’t think this driver can deliver that kind of bass sound but it delivers the kind of bass sound I’ve heard before from my “Apollo” DIY open baffle speakers.

I hope this is helpful:

FYI - After I built this speaker I more or less gave up trying to better it and so far it is still my main listening speaker although I still tinker around with stuff incl. horns.