Like Discovery Weekly from Spotify but better and free of charge

playmore.fish

#!/usr/bin/fish

function findsong
  lynx --dump "https://tunebat.com/Search?q=$argv" | grep " 6. https" | cut -d" " -f5
end

function findrelated
  set song (findsong $argv)
  lynx --dump $song | grep Info | cut -d/ -f5
end

function getsongurl
  lynx --dump "https://www.youtube.com/results?search_query=$argv" | grep watch | head -1 | cut -d" " -f4
end

# Ok so ignore everything before here
function playmore
  rm -f /tmp/songs/*
  rm -f -d /tmp/songs
  mkdir /tmp/songs
  set first true
  mpc clear
  for song in (findrelated $argv)
    youtube-dl -f 140 (getsongurl $song) -o /tmp/songs/$song.m4a
    # No need to wait for the others to download to start playing
    mpc insert file:///tmp/songs/$song.m4a
    if test $first = true
      mpc play
      set first false
    end
  end
end

# Will do this at some point, need to think whether it is necessary to get the
# mp4tags or not. Because technically we're deleting the files anyway.
# originally this was here due to the spurious characters from Youtube videos
# that broke Mopidy
# function rename_files
#   for file in (ls *)
#     set artist (echo $file | cut -d"-" -f1)
#     set track (echo $file | cut -d"-" -f2 | sed 's/[()]//g')
#     mp4tags $file -s $track -a $artist
#     set num (math $num+1)
#     mv $file (echo $num).m4a
#   end
# end

#if you're not using this file as a function / alias of Fish shell in the folder 
# .config/fish/functions then uncomment the line below. 
#playmore $argv

Newflash:

• You can save playlists and then load then with mpc load playlistname
  Notice that it is the name of the list, not of the file.
  Once loaded you have to play it so mpc play
• If you can find a way to save a youtube song to a playlist then you'll get the correct format to open them without downloading them.