I'd take Kim Irvine's work over the team that "transformed" Paradise Pier into Pixar Pier! Any day.. . . I think you may misunderstand what Kim Irvine's job is.
She's not a Marc Davis or Tony Baxter or Joe Rohde, proposing attractions and seeing their development through to opening day. She's an Art Director. Her purview is much more related to the existing menu of Disneyland attractions than it is to creating new ones. Her job literally is to try to maintain the integrity of the existing attractions despite changes being deemed necessary by higher-ups - whether they be creative executives or otherwise.
She makes appearances in these videos because she leads the art direction of lots of these smaller projects and is the most senior person to talk to about them, not because she's insisting on it to rise her star. We've seen time and time again that she's not particularly comfortable on camera. She didn't even WANT to do Madame Leota in the Haunted Mansion Holiday, she did it because she was assured if she didn't they would just hire some rando who had no connection to the park, so she took the opportunity to keep it in the family. And, truthfully, who doesn't love the fun fact that the HMH Leota is played by the original's daughter?
All this to say - most of these "50/50 changes" you're referring to were overseen at least in part by her. Give her credit for the lesser ones, sure, but then give her credit for the greater ones too. Much of her job is negotiating what stays in, leaves, and returns to the park's attractions as they exist. Some other Imagineer might have insisted on a new scene of their own design - instead Kim Irvine gave us something that had the history of the Mansion baked into it. We'll see if it plays out well in person.
You should have HEARD what they WANTED to do to Small World before she stepped in and convinced them to merely just add some Disney Characters to it instead. I don't love that change, but the alternative would have been FAR worse. But it's not like she spoke up out of nowhere and said "WE NEED TO BISMIRCH SMALL WORLD", as many would have you believe. That's not her job. Her job is to listen to what the Company wants the park to become and try to massage that into something that retains the park's DNA rather than changes it fundementally.