To invoke, use the following hotkeys. You can change the hotkeys to anything you want by editing the workflow.

Control+Alt+1 (or 2, 3, 4, 5, 6)

• In the Alfred dialog, press a number from 1-5 to apply stars.
• If you use 6, it applies 5-stars and a heart.
• You can also clear the current rating by pressing 0.
• Inputting a number less than 3 will automatically jump to the next track.

AppleScript was used to apply the heart. Everything else is pure Alfred love.