Upside to a serious flow program...
-You get to apply mainline hiring standards to the people flying your feed.
-You get to attract the most competitive entry-level applicants.

Downside...
-High standards at the entry-level are of limited use. You're missing all of that professional turbine and PIC experience. You're evaluating them on HS GPA and whether or not they got caught doing the usual stupid frat boy tricks. You're basically committing to employ a 22 year old for 40+ years. You could I suppose apply some gateways, ie flow beneficiaries have to maintain certain standards with regard to criminal, training, discipline, etc.