The problem with this approach is that it utterly ignores the fundamental realities of American politics: in particular that political power is utterly monopolized by the two major political parties, and that the system is such that competing parties will probably never be able to challenge them. The present in fact serves as living, ongoing evidence and testimony of this, a perfect case study of the resilience of the status quo, and the relative impossibility of any real third party upheaval. Despite record discontentment with the Republicans and Democrats and establishment politics, no third party has managed to ascend to anything close to representing a threat to the current political order, and there's no sign that this will change.
In the event that the Republicans and Democrats didn't utterly domineer the political process, including the avenues for reform which would permit for real change in the status quo (such as the elimination of First Past the Post, control over money in politics, etc), I'd be in full agreement with you. The simple, irrefutable fact is that democracy simply cannot survive in any meaningful form if these parties have strong or worse, absolute powers of filtration, therefore the choice is either keep those powers as marginal as possible, or embrace oligarchy. For me the former is a clear and obvious choice.