I personally think all of those options are fine. I voted for #3 though, because many local people I know that are interested in vintage, but don't normally play, are put off by the generally very top heavy prize structure of most vintage events.
That high roller side event thing doesn't seem like a good idea, but this is only my opinion. Maybe others would enjoy it.
I've had four guys who approached me with the idea of a high down, high reward side event.