On the technical properties there are no issues here.
On the practical considerations there are a number.
It requires explaining the Smith Set It requires explaining Condorcet winners It requires explaining Approval voting. It requires introducing two new voting methods , with two different ballot types, each with different instructions, at the same time.I recommend having one voting method only. If you want to have a primary and general then use the same good method for both and don't narrow it down too much before the general. That's actually simpler and will get much broader support from stakeholder factions and minor parties who want real choices on the general election ballot.
Condorcet is accurate enough to just skip the primary all together unless there are too many candidates. If you want Condorcet with a simple tiebreaker why not just make the tiebreaker between the finalists (tied candidates) automatic in the event that it's even needed? In the tiebreaker, each voters ballot counts as a vote for their favorite(s) still in the running. If a voter ranked two candidates equally that would count as a vote for both. The finalist with the most votes wins.
The tiebreaker never even has to be explained. It's literally just a built in tiebreaker like a Plurality provision might call for a drawing of lots or a coin toss, but the ballots already have the tiebreaker info they need so it can be done instantly.