The playlist you ask Alexa to play will depend on your mood or the occasion. Here are few suggestions:

1. "Alexa, play my Discover Weekly on Spotify." - This is a personalized playlist that Spotify creates for you based on your listening habits.

2. "Alexa, play Top Hits playlist on Amazon Music." - This will play the most popular songs currently.

3. "Alexa, play workout playlist on Apple Music." - This will play energetic songs perfect for a workout.

4. "Alexa, play Relaxing Music playlist on Amazon Music." - This will play calming songs, perfect for winding down or meditating.

5. "Alexa, play 80s Hits playlist on Spotify." - This will play popular songs from the 80s.

6. "Alexa, play Classical Music playlist on Amazon Music." - This will play classical music pieces.

7. "Alexa, play my Favorite Songs playlist on Spotify." - This will play a playlist of your favorite songs that you've created on Spotify.

Remember, you'll need to have the relevant music streaming service linked to your Alexa device to play these playlists.