The only way I've found to have effective 1:1s is to come armed with pointed questions about how things are going, and to actually be aware of what your reports are working on and who they're working with enough to know what questions to ask. They don't work if you're passive. You can surface a lot of vague feelings of unease or satisfaction with initial questions that you can turn into in-depth conversations, and those usually tell you what the person's preferences and areas of growth are.

I think no matter what structure you put in place as a manager you still have to get to know your reports well enough to know what you can and can't confidently ask them to do.