While I understand the reasoning and agree somewhat with the 2nd lead-off theory with the 9 hole, it depends on the individual. Not everyone hitting 9th accepts the 2nd lead-off theory and sometimes underperforms because there is always a stigma of hitting 9th. Some live down to that expectation.
IMO - I would hit Becker lead-off, think White is a prototypical 2-hole hitter but you have to put him there and leave him. Shelby 3rd and McNeil clean-up. Would move Pompey down to 5th as I don't like a freshman hitting 4th unless his name is AJ Reed.
Mahan would then follow in the 6-hole. Just move the others down. It's early in the season for both pitchers and hitters. Think Henderson is still experimenting and the Cats will get some losses until the coaching staff can get a feel on who can produce in what situations during a game setting.
Say what you want, but until you get outside on a regular basis to take live pitching, it's difficult to field a consistent lineup -- UL notwithstanding.