Previously, there were people like Tan Cheng Bock, Tan Soo Khoon and Ong Teng Cheong. They spoke up without fear, according to their conscience.
In the current batch, there is Denise Phua and Lily Neo. You also cannot discount the possibility that some of them are just keeping silent about their true views. I believe that Tan Chuan Jin may be one of those who feels that the PAP needs to change its ways and if he were PM he would discontinue alot of the disgusting practices that we see today. Time will tell as he is still new. But I feel he is someone with political ideals, not just a technocrat, unlike his good friend and former SAF colleague who is a pure policy-oriented technocrat.
However, alot of the newbies are just bureaucrats and not really politicians with principles and stands on issues.
Tan CJ won't change things. Georgy Yeo wanted to but thought better and stopped short. Change or no change, Georgy got booted out. So TCJ doesnn't want to face a GY situation yet--although he will since he's in GCT's group. He's after all another BG...