You can change the rain refresh rate by modifying the rain.animated file.
Railway\Object\Crosstown\rainobj\rain.animated is the location. Where it says RefreshRate =
[Object]
States = rain3.b3d, rain2.b3d, rain3.b3d
StateFunction = mod[value + 1, 3]
RefreshRate = 0.1
Make that number smaller. Do use it with caution though, as my computer crashed when I set it too quickly, or its just my laptop (most likely my laptop).
If SIR grants me permission then I will work on a R160 version. I have heard his announcements however, and there were some issues with it. I believe that train was terminating at Coney Island and not Smith-9th which would make it less likely for me to use it, unless I made more modifications to it. The announcements issue will be fixed on the next major update then, which will be who knows when.