I have good news and bad news. The good news is the skill portraits were not changed - the revised versions we saw on Displate were apparently just versions made exclusively for the merchandise and were not implemented into the game for some reason. The bad news is the skills all talk in that same garbage monotone with classic mode on, and it is indeed very garbage. That's not to say Classic Mode is "broken," though.
The skills don't talk universally in classic mode. They only talk when the game considers it to be "important," and what the game considers "important" is particularly scattershot, arcane and impossible to figure based on what little I exposed myself to. For example, the perception check for finding the keys isn't voiced, even though this is pretty damn important considering it's how you, y'know, exit the room. Endurance isn't voiced when you have a heart attack, nor is Pain Threshold when you turn on the fan light. Encyclopedia doesn't emit any sound when you fail the check to determine the origin of the expression, and the entire Visual Calculus bit with the window is unvoiced save for the line at the start. So this lines up roughly with how Hongweibing described ZA/UM's idea of Classic Mode a few months ago, but it's still royally ass.
I'm going to spend tonight giving myself a shotgun course in Unity modding, I'm flying by the seat of my pants with this one but I'm not settling for anything less than OG voiceover and damn if I'm not going to find a way to do it!