Can't really speak to any successes so won't share specific strategies, but from what I've seen there is very much no one-size-fits-all. The best options vary a lot depending on the target audience, differentiators and even the temperament of the founders themselves.

Try everything and keep doing what works for you, I guess.

I'm in the camp of "Don't build it unless you are talking to your future customers", so launch is always fairly simple - let them know it is up.