For me, for running lots of short-lived wine processes, the single biggest speedup comes from running a persistent wine server. Without any wine processes running, run "wineserver -p". That wineserver instance will then stay around (until terminated with "wineserver -k"), greatly reducing the startup time for each command.
That's a very good point.
(In my case, wineserver was already persistent, because all my other processes were descendants of a wineconsole.exe process)