A random thought but why not.
As the very first mons that we get in the game I think they definitely deserve an icon once they reach their final form.
To make it even more significant u guys can give the icon while choosing the mons at the start itself so that we have only 1/4 icons .
That’s a wonderful idea bro!
Or the developer can create a nice combined icon of the 4 Starters, which you get, once you own an ultra evolved Chronozeros + the UE Forms of the Starters.
That would maybe raise the interest in doing this complicated evolving Chronozeros/Starter task.
Tbh i have 4 years in the game and i never capture Chronozeros and i have the 4 starkies as decoration🤣
And i think that if they bring a new icon for that i will not play for got 
But the idea of @Unholy_Prem is good
I’d love to get myself a Galvbane icon.