Tharman is the only cabinet minister who is of prime ministerial calibre. All the rest, including Pinky, CMI.
He's a closet liberal. A little-known fact is when he was studying in England, he (and George Yeo) used to meet up with Tan Wah Piow for tutorials on Marxism and social justice. He's just biding his time right now, subverting the system gently from within with increasingly redistributive budgets year by year. But he'll only show his hand when the PAP breaks up.
If the PAP splits in the near to medium term, very likely now that old fart is gone, expect this Jedi to lead the breakaway liberal faction. That may be Singapore's best hope for salvation, given the fragmented state our opposition is currently in.
Watch this space.