Color gradient or number value for distance in allied player move marker

So many times have I tried to work out timing on ganks and rescues but am too busy to check the map.

Situation: In an intense skirmish with timing for dodges and attacks at their limits, a friendly suddenly sends a move ping that (s)he is on the way. There is no way to know in that instant what my next reflex is going to be. Do I kite, or all in?

Solution: Color the move arrow triangle from to color A to color B to show how far away that player is. Either that or add a rough numerical value of the distance.