Not sure, maybe try the knave role, haven't seen it being played out much in the forum games I've played. Fast talking guy. Sometimes I figure other skills like procurement and trade would be better than the skills I have seen on the book.

I've never played PbF ...

Me neither, I'm hoping it involves a lot of sitting in my pants eating croissants whilst playing (something with which my new gaming group probably won't let me get away...).

There is a Trader path for the Knave in Cadaver Draconis ...

I hadn't even thought of mining Cadaver Draconis for character inspiration - I might have a quick read-through of the sorcerer paths to see if anything inspires me.

I was thinking of substituting Bedevil (from the Players' Guide) for one of my starting spells, though, as it feels like a more suitable spell for a young city-born sorcerer and in keeping with the vision I have for him - I've always preferred the subtle approach to sorcery than the big flash-bang spells.

There is a Trader path for the Knave in Cadaver Draconis. Some of the skills from there could also be made available to a more traditional Knave...

I don't have the Player's Guide (although I have found Cadaver Draconis) - is there somewhere I can find the basic rules/spellbooks for the new professions and alternative spells?

I know that the description said vanilla rules from the core rulebook, but will the game feature homebrew stats like Constitution and Size rather than using Strength for multiple things?