Thanks for the ideas. In my experience, press releases don't do anything. There's just a million of them, and the only ones that get picked up by the mainstream are probably ones with lots of novelty value.
I could add a couple more puzzles in an update, but in terms of reach, I can't monetize people who have already purchased an unlock, and if they haven't already purchased the app, they probably won't despite the update (just a guess). I might get some sort of app ranking boost from the people that update, so I suppose that might be worth it.
In the case of building flash / web assets, I'd have to go out and build those and then promote them as well. An incredible amount of work where my goal was just trying to drive app downloads + unlock upgrades. I don't think such an indirect path is feasible when I make only $1.99 on a purchase. Like I said, app marketing is goofy :(