Core principles are not relevant after the primary.
To tenaciously hold to them and vote for a third party or not vote because there is no candidate that meets all of your requirements is a cop out. It is hard work, but after the voters have chosen two candicates in the primaries, one must weigh and measure which of the two to vote for.
We are not Israel where we have many splinter groups and tons of candidates. We are America with two parties in the Presidential election
If they are not relevant, then they are hardly core.
It is harder work to make an unpopular decision based on true core principles (such as support for the first amendment) and to stick with it than it is to throw away your beliefs because of a candidate's party affiliation.
Good luck with your fungible tenets, FRiend.