Well, the Syndicate Wars port has shown no signs of a new version being released, so the speed problem is still present.
For reference, see this thread:
https://groups.google.com/forum/#!topic/syndicate-wars-port/sVDHowuiXcs Unavowed, one of the developers of the port, has even posted a patch file to fix it, but you have to compile it yourself. The instructions for compiling it just don't make sense to me, though, as they are nowhere near detailed enough and so assume a lot of compiling knowledge as a pre-requisite.
Using the text from the patch file I've been able to edit the relevant lines of code in the source file, but without knowing how to compile it I can't push this any further forward.
So, anyone have any idea what you are supposed to do to compile it (I'm on Windows)? Or would anyone want to try to compile the edited source file I have?