Glad to see all of the interest so far!
To answer some questions:
Appraise, Craft, Perform, Knowledge, Profession, Handle Animal, Heal, and Linguistics all have commercial value as skills. Hell, spellcasting by itself has value. Prostitution requires little training or a certain class. I *hate* saying this, but I am going to be completely arbitrary when it comes to judging whether or not the character is "commercially viable." Basically, I want a group of characters that make sense as part of one company, and I want to see some effort toward making the character fun as opposed to powerful.
Korvosa is LN, with the lawful being the most important. I'd like to see some variance in alignment, but no zealots or overly chaotic types as neither really fit.
As for classes, I'm not crazy about summoners, but I don't feel like saying no to them. If you can be patient with an inexperienced GM lacking a bit of natural talent, I can at least not be a dick about published, playtested rules.