That mosaic concept sounds terrible. All the windows moving whenever a new window opens? That just sounds very annoying and very bad for my spatial memory.
It's called dynamic window management, it's very popular, and that's without the animations showing you that something got moved.
Imagine a desk in a windy park. Maybe the next innovation from the Gnome devs can be a "paperweight" you can drag onto your windows to keep them from blowing away.