Yes, it can be used for Compassion/Lovingkindness. Groups of people; alphabet with occupations, we think of all airplane pilots, we give them a nice Compassion/Lovingkindness wish, we think of all bankers, we give them a Compassion/ Lovingkindness wish, all cooks, all doctors and so on. Yes, by all means, you can combine it with Compassion/Lovingkindness. The more interesting you get with these different types of reflections, occupations, alphabet, ages from 0 to 100, body parts, people missing toes, people missing feet, the more interesting you make these systems, the more interested you get with these meditations, then the more concentrated and mindful you will get doing it.