Not sure I agree that it's critical to get it right first time, but at the appropriate time.
Even if you have incorporated, it is possible to do a NewCo later with a different structure and roll the startup business into the NewCo.
Your company incorprated name does not have to be the name that everyone knows you by (trading name/site name).
Isn't this what Facebook did when they needed to bring in further investors way back when?