While not historically accurate, I think that area of any acoustic guitar with otherwise standard X bracing and a standard neck block would benefit from a trapezoidal patch. Just search here on the OLF for the word trapezoidal and the discussions should pop up.

In order to accommodate a truss rod that adjusts through the soundhole, I build my trapezoidal patches in three pieces: one on each side of the space needed for the adjustment, both pieces a little thicker than the space I need for the adjustment wrench, and a 1/8” cap over both to close it in.

I think the main problem the 'popsicle stick' brace was meant to address is cracks in the top along either side of the fingerboard. The ebony fingerboard shrinks for a long time, and will pull a crack in the top on either side where it runs along a grain line. This weakens the top in the area that is under the greatest stress. Without some sort of reinforcement the only thing keeping the neck from shifting inward is the glue line between the upper transverse brace and the top. Often it's not up to the job, especially if the guitar gets dropped or falls backward off a stand.

In theory the large glue surface of the popsicle stick brace should keep this from happening. In practice it's often not as effective as you'd like. Most of the 'modern' glues, such as Titebond, will 'cold creep' under a sustained shear load like that: I've seen guitars where the neck has shifted inward by 1/16" or more but the glue has not actually let go: it just flowed. White glue is notorious for that, and at least some manufacturers have used it. Hide glue doesn't creep, but it also has low shock resistance, so it will sometimes let go when the guitar is dropped.

The best solution is probably to use a brace of some sort to take the load in compression. Some folks use a 'flying buttress' between the neck block and the waist, sometimes of carbon fiber. Others have use a column between neck block and tail block. I've been using an 'A' brace setup for decades now. I'm pretty sure it's effective; I've had a few come back for visits that have been dropped or fallen in ways that should have caused the neck to shift in, without any sign of it. I use a couple of braces that are about 5/16" square in section, glued to the top, that would converge on the center line at the upper edge of the top, and run outside of the soundhole. They are inlet into the upper block for 1/2" or so to their full height, run through the notched UTB, and end at the upper arms of the X. I also use a doubler around the sound hole in the space between the UTB and the X, bounded on either side by the 'A' braces. The lower ends of the 'A' are taken down to the height of the doubler (usually about .100") and trimmed down to a low triangle that gets inlet into the X arms. In theory, if you fit it well, this should take up a lot of the compression load of the neck and distribute it around the hole, preventing the neck from ever shifting forward. We'll know for sure if it worked in 75 or a hundred years....

That does not address the issue of fingerboard shrinkage, though: you can still get cracks along the sides. For that, in part, I use an extended 'chin' on the neck block that runs most of the way down to the UTB. It's made 3" wide at the upper edge, and tapers down to 2-1/2" wide, about the width of the end of the fingerboard, at the lower end. This keeps the edge, which sticks out past the sides of the 'board, from running along a single grain line. It's still possible for the board to shrink and pull a surface crack in the top, but at least it should not weaken the area. To prevent that I usually only glue the fingerboard down to the top in the center.

One complaint I've heard about making "tall" braces around the soundhole is that it makes some electronic systems difficult to fit ( I still generally use them). .................

I use 2 angled braces, the upper end butting the neck block, going under the A brace, (too late for you) angling beside the sound hole, butting the upper X legs. I have used this pattern for many years on all my guitars. I think it is the answer to upper bout deformation.
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