If you feel like you’re wasting too much time thanks to Mission Control’s animations, use these commands on the Terminal to speed it up:
defaults write com.apple.dock expose-animation-duration -float 0.2
You can change the 0.2 value to whatever you like best, and if you want to return it to the original speed, just use these commands instead:
defaults delete com.apple.dock expose-animation-duration
Thanks to @bdc for the tip!