I think a wind sock wuld be a very nice touch to see from the tower.
As for the wind direction on the knee pad? I'm not crazy about that idea. You should be able to get the "weather" info from the tower before flight and keep it in mind when you fly.
Being on the clipboard and readily available 100% of the time runs along the same lines as the super accurate phased array radar we have now. Neither is very realistic.
Just my .02....
-Westy