My understanding was that the Prominence mechanic isn't meant to play much of a role in republics (it might be a Rome-specific thing?). But prominence for other nations' characters is displayed below loyalty (where the first instance of the Statesmanship display is - which is actually useful there, as the bottom bit isn't shown in the character card that now appears if you hover over a character's portrait, as opposed to clicking through to their 'profile').
Senate power (the 29.3 in the OP's image) would also be fairly useful in the character cards, to be fair. It's not as though there's no space for it - why not list prominence and senate power (if applicable) in the area below power base/wealth?