Really like your idea. Not so much the lack of TT bikes, I wanna see them thundering along at 60km/h, but definitely force teams to have more versatile riders.
I remember a story of Julian Dean, when he raced for Garmin-Chipotle, who had a big TTT focus. He was the “last” rider left, when he really wasn’t supposed to be. Lead out man, swinging on the back to make up the required four. I might be mixing stories, but I think that was his only GT stage win.
I love the stories it can create.