Imagine a hypotetical calculator reissue. Imagine now that you are confronted with the following question: would you keep the calculator that everybody loves exactly "as is", or would you try to improve upon what many have considered the perfect calculator?
Picture yourself as well confronted with the fact that everybody else wants new calculators being developed (refresh the graphic family, low end and high end, etc.), and that this reissue has strong appeal only to a small group of engineers (around 100.000 units were produced in its first incarnation).
A new development to extend the features of that loved calculator (like including algebraic entry, multiplying its memory) would detract from your current development programs. The fact that the original firmware is there only in the form of a ROM, without any other documentation or support, does not help, either.
According to the information that we have, it comes as no surprise that the firmware would be exactly equal to the original model, i.e. limited to 65 registers. HP would think it's better to avoid glitches and problems using a proven solution. However, according to a source linked to emulator design, it would not be too difficult to move it up to 128 registers. More than that could be substantially more complex. But that might be our community's task (the reissue would come with the same adaptor found in the HP30b)
If you'd plan to go that way, it would be good to buy 2 calculators: one to experiment with, and the one that stays "factory" (you will not be able to keep the original firmware once flashed)
Just imagine what can be done with 128 registers! Or imagine if you can have 2 memory spaces- just like what's been done with the wp34s: you could keep 2 sets of programs according to your needs; or have one set with your programs (close to full memory used up), and one set empty, for heavy matrix utilisation.