Congratulations to you and your Daughter, sounds like a great ride!
With the shortblock being put together at factory specs, i'm not sure if a cam swap will be worth the investment. Valve lash on a engine like that will usually hold for a long time. If your set on converting to a hydraulic, i'd consider the cam that "Abodybomber" suggested. Just remember that the adjustable rockers will still be part of the package unless you switch to stamped units at the same time.
I think I'd let her run as is and just give her as much initial timing as it will take with the hi compression on pump gas. Keep in mind that the best mileage on a combination like you have is from the tune and the right foot. Easy driving and keeping the rpm's down will do more for mileage then any component swaps with your current combination.