[Idea] 2v2 pinging your team mate

We can all agree that we all love 2v2. The most frustrating thing is not being able to communicate / coordinate attacks with your randomly assigned team mate. A simple solution is to have a ping button. It's function would be similar to playing a card - you click it / drag it anywhere on the map and you and your team mate see the ping

Some examples of it's use:

-If I'm starting a heavy push (golem) and the opponent tries to jam the other lane, I would ping the other lane hoping my teammate would give it his all to defend the other lane and not support my push.

-If I want my teammate to focus on attacking or defending the right or left tower

-Ping the area where I would be placing my tower or troop or spell so we don't place in the same area

I think this would be a very simple yet useful feature to have. I don't have any suggestions on where the ping button should be placed as I'm terrible at UI design, but I think it would take 2v2 to another level since we would be able to coordinate to some degree.