I'm worried that such a list would be fairly light on 'heavy-weights'. Maybe Mr. Graves or Barbaros?
Also, start with the Poltergeist or not? Trying to summon it in the game saves stones, but I feel the advantage it can give is too big to leave it out.
Maybe something like this?
Pandora
Woe is Me, 2SS
Cry for Me, 2SS
Depression, 1SS
Poltergeist, 5SS
Barbaros, 10SS
A Thousand Faces, 1SS
Mr. Graves, 8SS
A Thousand Faces, 1SS
Iggy, 5SS
Field Reporter, 4SS
Field Reporter, 4SS
Will O' the Wisp, 3SS
Available Soulstones: 50
Total: 46
Pool: 7
Alternatively, exchanging Barbaros and some cache for any two of Doppelganger/Tannen/Lilitu?