I have a blog post that I took this from. It should give you a good idea of topics that your letter writers could talk about. Hope it helps😉
"3. Things to talk about in a letter of recommendation
Some of the professors or dentists may have never written a letter of recommendation or have written very few. In some cases the professors may be writing letters of recommendation but not really know what they should write about. That is why you should hand them a list of things that can or should be included in a letter of recommendation. This list should not even be much more than ten items long. I will list some ideas but feel free to come up with some of your own. You do not have to include all of them.
Maturity
Academic potential
Problem solving skills
Ability to handle stress
Adaptability
Communication skills
Ability to exercise good judgment
Self-confidence
Resourcefulness
Compassion
Work ethic
Critical thinking skills
Capacity for empathy
Motivation for learning
Understanding of the profession
Motivation for the profession
Interpersonal skills
Integrity"