I don't regret my purchase, either. Still, it was a lot of money to spend, more than what quite a few people are willing to pay. Like you I'm really looking forward to Gravity Rush! I doubt I'll really play the Vita much again until then. Oh, but I do need to download the Escape Plan update that adds prequel levels, and fixes some of the controls!
As for PSOne games, I'm not sure when they are coming. E3 is coming up pretty soon though, so I imagine that would be a good place for Sony to announce a date for that functionality.