I can't claim to be heavily invested in this issue, but I think one of the better short characters to have a potential romance with would be Thulla.
As for Barcus, I can see the appeal of having him as a companion, but I don't know. Part of his thing is that he's not a qualified adventurer, which is why he needs to be rescued by the players. Also, I wouldn't want him as a companion unless there happened to be some class mechanic that allowed for the creation of smoke powder bombs and inventions in general.
