I think the Vita problem is that most people use their handhelds at home.
Making the console gaming on the go moniker and focus a mistake... since your competing against consoles in this case. What you want is mostly games that are different.
Additionally, if I am on the go... I don't want a console game... because i'm going to be interrupted constantly. I want a game that has more "pick up and play" qualities that i can pause a lot.
If i'm just going somehwere and spending a half hour, hour playing a game. More likely then not something has gone terribly wrong.