Treating someone as a person, rather than a resource. If it were happening to you, what would you hope for?
Or even better, I'd hope for a written email explaining the detail instead.
I never encountered a layoff. But I encountered several rejections after on-site interviews.
And, every time, the recruiters insisted on talking on the phone. It wasted my time. Scheduling a phone call required scheduling it the next day and finding available time and etc.
Just tell me the outcome. Personal communication is great, but it shouldn't waste people's time.
Do you know the worst thing about a layoff, knowing that people are being laid off and not knowing what's happening to you or the details of the layoff. In your scenario, the first few people who were laid off are very likely going to reach out to their work friends and soon everyone knows there are layoffs, but no one knows who's getting let go. So you do you prolong this suffering, or do you make it quick and provide a way to ask questions afterwards? I think quick is better.
I've been through an in person layoff, and nobody spends time with those who are leaving. We did the visit each person and tell them their fate, and it sucked. But we spent only a few minutes with each person, because we had to make it relatively quick. Everyone had to wait in their offices to find out their fate.
No matter what way you choose, there is always going to be an armchair quarterback saying the way you did it is wrong. Layoffs are hard and there is no way to make everybody really happy about them.