You are so kidding on so many levels, right? Right?
To "succeed" at doing anything within the federal government, Barr would first have to have one-one-millionth of a chance of being elected, which he does not.
Then even if he somehow got elected, he would have to have one-one-millionth of a chance of anyone in Congress of either party giving a rat's patooty about what he thinks as a president with absolutely no coat-tails and no party structure, which he does not.
If Bob Barr or Ron Paul were to somehow (Please, God, are You listening???) to be elected, do you not suppose that the whole Congress would fall all over themselves, at least for a while, to pay attention to what We, the People, had said by electing one of those two instead of the party hack? Especially if the new president’s coattails pulled in a few CONSERVATIVE congress critters???? I suspect they’d be all over the Conservative/SMALL GOVERNMENT agenda for a while, so a lot COULD get done.
Plus, of course, the VETO and judicial nominations which would shore up conservatism for a long time to come.