Many times online we read of Bernie or Liberty Media wanting to grow F1's presence in the USA and they both have referred to it as a "tough nut to crack". So much time and money has been invested into picking locations, tracks, etc, but I honestly think F1 is missing one major point.
In order to grow F1's appeal, the cars must be able to make bigger drivers competitive. No offense to F1 but only drivers who have horse jockey physiques can compete to win.
How many "average" people (not just in the USA) have bodies like F1 pilots or MotoGP riders? Not many (this includes me),
So F1 has a much better chance growing their presence in the USA if a driver with a body like Tony Stewart, Juan Pablo Montoya, etc can compete with the "featherlite" drivers like Seb, Lewis and Co.
Make rules that allow bigger people to be competitive. Its not that hard.