Let's not confuse fact with hopes.
Russia is the largest gas producer, U.S. second, Canada third.
It is entirely possible with Exxon's and other recent discoveries and magnificent projections of additions to reserves that the U.S will indeed have more access to natural gas (Exxon's world-beating shale gas find is in Canada, at least a friendly country).
As in other discussions about energy, care must be taken not to overweight a solution. In the 1990"s natural gas availability and projections led many energy economists to offer natural gas as a solution to energy needs for power production, and home heating.
Guess what? People believed, millions of new natural gas home heating units were installed, additional power production plants went on line and...wait for it...here it comes....natural gas demand grew rapidly, leading to price increases of a substantial nature.
Now, we are in another cycle of discovering more natural gas (because we looked for it!) imagining the future as a natural gas heaven, and it just won't happen. Natural gas is still an "extractive" resource, still a diminishing resource, and in the long run, gas, like oil, will go away.
We need Nuclear for power generation for commercial and some residential, but energy self sufficiency, even environmental self-sufficiency on a per-household basis will wind up being the goal, and the necessity.
Much of what you suggest is being done-vehicle conversion, hybrids- and more is on the way. But there is not enough natural gas to thorougly exploit the opportunities you envision.
One other note; we are rapidly approaching the law of diminishing returns in regards to energy resources in which decisions must be made as to "highest-value usage."
This means simply is a gallon of oil more valuable as a fuel, as a lubricant, as a feedstock for chemicals, or for other uses? We may get to the point where oil's highest value is as a lubricant for the wheels of vehicles using electric engines-direct drive-which also need lubricant.
Your thinking about the solutions is the best guarantee we have that America will be the leader in creating opportunities for energy self-sufficiency, and then independence.