I've reread your post. Maybe what you are saying is that you asked Ed to come out with a newer firmware to change the behavior of the temperature averaging, and Ed said no. If this is the case then I don't think you have any options other than to not use that display console. You could do things like trying to pull data directly from outdoor sensor array using an SDR. Or you could try using the ObserverIP device instead (but I've noticed temperature averaging on that device too). The best recommendation is to do what you've said which is to get a newer station hardware.
For what it's worth the newer WS-2000 and WS-2902A update rather quickly and there is no noticeable temperature averaging compared to the ObserverIP. I don't have experience with the WS-1001 generation devices though.
To Ed's defense, the WS-1001 is discontinued. The display I think is similar or same as WS-1002 (older generation still). I think the focus lately is the newer generation that use the Osprey outdoor sensor array (WS-2902A and WS-2000). It would be hard to justify any improvement to a discontinued model, especially when it isn't broken, you just don't like how it works. It is also possible that there is a limitation in design because the 10 minute averaging you have noticed could be tied to the rain rate calculation which is based on a 10 minute history. So maybe there is some internal loop based on 10 minutes, where if you mess with temperature you affect or break rain rate. So it could be more complicated to separate the two. Even if not, old discontinued products get no love (more so when they aren't really broken). Want better?... Then upgrade to newer model.