I interviewed last week with a regional. Ask about anything you legitimately have questions about and isn't readily available via Google. Here are the follow ups I went with:

Is it reasonable to expect ERJ-175's out of DFW for new hires? Yes, generally picking domicile for new hires and most go 175.
Reserve time estimate? 0-3 months for 175's, 3-6 months for 145's, up to 9 months for CRJ-700's
Effect of the shortage on the average pilot? Quicker flow
How is performance evaluated? Captain inputs a grade from 1-5 on various traits for your first year.
How did you get your start, why do you stay? Long story, then basically for the flow vs. swapping airlines.