After a sufficient number of leftists have moved on to the Green Party, it will then be OK to create a truly conservative party without throwing the election to the Democrats.
A conservative party wouldn't necessarily need to field its own candidates. It could agree to support the Republican candidate if that candidate is sufficiently conservative. Just like the Conservative Party of NY often does.
This will take a bit of time to take effect, but it is better to help to split the left before we split the right.
The most fertile ground for a true conservative party would be in the southern states where Democrats are weak.
The local GOP RINO leaders who created those proportional primaries deserve replacement.
They set up the scenario so Romney could win delegates down there.
Back in 1976 Reagan took Texas as a winner take all. This year it was made a strictly proportional primary.