Something I'm trying this year during class discussions is using ice-block/craft sticks with student names on them to randomly select who will answer questions. This ensures students are all involved as statistically everyone will need to contribute in the course of a lesson/week.
Students are allowed to pass, and I reserve the right to answer the question myself if too many students pass (usually three is my limit). Students who pass will have to repeat what the next student says or what I say so that they don't immediately disengage once they pass.
I'm also trying to ask the question before I select the student to respond as this gets everyone thinking because there is a very real chance they will have to answer.
Regarding Christian lovingkindness toward the students, I am ensuring they must get involved (even when they don't want to) which is good for their learning. However, with the option to pass and repeat back a fair system is in place that does not embarrass students, respecting them as image-bearers of our God.
So far the feedback from students has been positive with many enjoying lessons more, with a sense of fairness at who is asked to contribute. High contributors are also welcome to add further thoughts so that they can continue to express themselves in a way they are comfortable.