Is there any way to configure TeXmacs (either at run time or while compiling it) to further reduce keystroke latency?
One idea that might help, especially on older hardware, would be to provide an option that instructs TeXmacs to delay certain aspects of the rendering of complex formulas until the user explicitly requests it.
Another idea would be to offer an input box where the user could enter ASCII markup (TeX or Asciimath) and wait to render the content until after the user is finished entering it. This approach would obviously represent a big step away from the overall goal of providing a completely WYSIWYG experience, but it might nevertheless provide a useful stopgap measure for experienced TeXnicians to keep using TeXmacs until the rendering algorithms can be further optimized.
Also note that the problem with latency here is not limited to complex formulas. A fresh install of TeXmacs on Windows with decent specs (12 GB RAM and iCore7) has greater than 500 ms keystroke latency in basic text mode, which only gets worse as the paragraphs grow longer. One would hope that there is still room for improvement here too.
TeXmacs is a fantastic effort, but these persistent latency issues continue to prevent me from switching over from Emacs + AucTeX + LaTeX preview mode after all of these years.