As far as I know, pings were made to facilitate communication between the teammates. And one thing I hate is when I have to pay extra attention to enemy ganks or mispositions, type and farm at the same time, just to tell my jungler "there's an enemy ward at wraiths". And sometimes I end up getting caught because I wasn't paying attention while trying to stop my jungler from running through the enemy ward and blow away our gank.
Another thing is when bot lane for example didn't ward properly and the enemy Blitzcrank for example could roam anytime and secure a kill on me in mid lane. Everytime I have to type in chat "Ward here" and ping our bottom tribush like two times, which bothers me aswell like above.
This is why I suggest 2 new pings: "We need a ward here" and "Careful, enemy ward here". I hope this idea gets considered as I believe it'll improve the team communication as much as the latest pings ("Champion X is coming here" to let your friend know you're ganking) did.