On topic:
- Slash the price, and cut the price of memory cards. Advertise the price cut.
- Advertise better in general. Particularly playing down the "console quality on the go" thing. Advertise PS+ instant game collection a lot.
- Make sure they don't rush the games that are in development. We don't need another Black Ops Declassified (although, Killzone Mercenary has been in development for long enough that I think that won't happen).
- Work harder on getting the big Sony franchises to it. Gran Turismo and/or God of War next year would help massively. Uncharted Vita 2 with co-op and competitive modes would help. But more handheld-friendly titles would be better in the long run, like Patapon or Jak/Ratchet.
- Hope that whoever was employed before me had secured some third party support early. Particularly Metal Gear Solid & Grand Theft Auto.