Experienced units

Hello, i have this idea, give a small bonus to surviving units, like +1 atk or +1 def, if a unit has survived more than 5 battles, the unit should be better than a regular one, it would not be too much since the units die pretty quick, but when rushing, or in closed battles those units could make the difference. what do you think?

Yea if you stack units with 40+ and they win always in battles.So the stack would be OP. And it would complicate the whole game so really no support.

Already suggested, devs already say no.