Like if May didn't get together with Ash, I think she probably would have ended up with Drew.
Misty didn't end up with Ash I think she would get together with Gary or Tracey [I'm not a big Tracey fan though].
May I think would fall for Drew since he did give her those roses. So he at least likes her. She might return those feelings one day for all I know in Johto.
Dawn, well I'm a pearlshipper but she could possibly get together Kenny. They have the whole same goal in mind.
Iris... well to be honest I haven't watched much with Iris yet. Maybe 2 or 3.... I recently got back into pokemon so I have like 12 seasons to watch. She might go with Cilan.
So your thoughts???