I would be interested in a few of these. Off the top of my head, these seemed like the most practical choices for me:
I could offer
Cassandra for some sort of combat tournament. She's a very talented fighter with a lot of tricks up her sleeve, as well as some badass armor and weapons xD
For the Uthlyn Crime Ring, I could offer
Kira. Though she technically lives in Zantaric, she has had to travel all over the continent for different jobs (all of which involve some sort of criminal activity, whether it's drug smuggling, assassination, kidnapping, etc.) so it wouldn't be too hard to have her get connected to this crime ring in some way.
I have a few new character concepts in the making that might fit some of these as well, but I'll wait until I've finished them to bring those ideas up.