Fun discussion, and obviously there are not really any wrong answers (other than Yuni B, that's definitely a wrong answer ;) ).
For me, the heads on the mountain have to be franchise icons. While CC's impact was huge and the performance over that few months was ridiculous, I can't put him on there with Yount and Molitor.
I appreciate the arguments for and against Braun. I think if are limiting it to 4, eventually (for sure if they win a Series), Yelich supplants him. Given more than 4 slots, Braun is the natural icon from the previous generation; Yelich is the recent/current, and Chourio is the heir apparent.