Yes, the WS-2902A seems to do better than the older model WS-1400-IP in a lot of ways. Besides the better humidity sensor, the wind vane seems to track more steady wind direction. Also the anemometer seems to pick up very low wind speeds. Graphs on WU also seem to have more data points or look smoother so it seems it reports more frequently (may or may not be true this last point, but it seems like it to me).
Humidity sensor in the WS-2902A seems to hit every step of those high humidity ranges; 94, 95, 96, 97, 98, 99. Granted the specs say it is only + - 5%. But I think it seems to be doing a lot better job than VP2s around me with their troublesome SHT31. This translates to better dew point calculations, and accurate feels like temperatures.
Let's hope the outdoor array proves to be more durable also.
The overall design of the WS-2902A is more appealing. The WS-1400-IP just looks like a cheap plastic toy.