Poor Oliver, he really got neglected even after he made it to full CGI.
Come to think of it, Oliver and Toad essentially ended up in a position that was a complete 180 to where they were when we first saw them - Oliver had a significant role while Toad was just a prop until Toad Stands By. Now, Toad has more of a significant presence while Oliver is just the engine pulling him.
Wow. I honestly never thought about it that way @ PolVio211. That's honestly really depressing, but in the CGI series, you can just tell they hated using Oliver, especially in instances where there where perfect moments for him to speak (ie The Missing Breakdown Train).