Spotlight and Mission Control (and the dock) being separate is good, and them being tied together on Gnome is horrible.

I just want to type which app to launch or do some quick math or search for something, I don't need my windows and UI to fly in 14 different directions and then back again every time I need to do those things. Ditto for just want to lazily do something on my dock with the mouse. It's seriously one of the most ill designed off-putting UX things about Gnome.