If it were me, I would go ahead and teach the remaining heart words that your kiddos have yet to learn.
Be sure to send the rings home to practice. You will be surprised how quickly they will learn the words.
As far as where to begin, I would start with the pink words. These, I feel, are the most powerful for kinders to learn. I would also include the words because and friend in that set. Only you will know that it they not pink heart words.
You could always customize the students’ sets to include the words they have yet to learn, a lot of time and work but worth while.
Just an idea.
When you implement Nellie’s ideas, you will be so surprised at your students’ success.