The problem is the Dems will never allow it AND they seem to have a locked in 43% minimum which guarantees they win three way races if they didn't just strangle the new party in its political crib.
You are assuming, of course, that a Republican party would still exist.
If the base of CONSERVATIVES moved to that party, the Republicans would turn into a joke.
It wouldn't be long until it was back to a two-party system with Conservatives v. democraps.
And, I'm pretty sure we could beat 43% heads-up.