I need some feedback on my plot idea and main character - I just need a little constructive critiscm etc.?

What are the ramifications of the ruby being stolen? Perhaps it's magical property is essential to the wellbeing of the city. Maybe There is an evil somebody who couldn't steal the ruby before but always wanted to, and now that it's out in the open he also goes after Farrell. So now she's running from both of them, and it's up to her to keep the ruby and destroy the kingdom, join the prince and defend it from the evil person, or join the evil person and take over. Just a thought.:) Armand can be the evil somebody. But I think she should hang on to it for a little longer, just to make it interesting.