I agree with Burflyer. I've heard from a pilot working at one of the most desired companies in the pt121 world and he says the best option for someone right now is to fly fractionals, not 121. If I was you I would go ahead and try the regionals unless you are 100% sure you want to fly corporate. If that's the case I would forget about the regionals and try to get a citation/learjet gig or get on a 135 cargo, then apply for something better.