As an E5, I will have 1:1 meetings with E4s on the team to lead/mentor them. However, I find myself running out of time in the meetings sometimes - What can I do to make effective use of all the time?
As Rahul said above, coming up with an agenda and not covering status updates is a good way to make these teams more effective quickly. Just make sure to let them know that ahead of time in case they are confused by the sudden switch in topics.
In general, I would try to figure out what do you want out of these meetings? It sounds like you would like to use these meetings to prioritize/align work for these folks? Maybe some of it is career growth? Once you have the goals of the meetings sorted out, the agenda becomes rather easy to come up with.
I would also ask them what they find useful. Different people need to be supported differently. Some folks like to bounce off ideas, others want more guidance, others just want to focus on career growth. You'll need to modulate what you do with each teammate yourself.
It's great that you are reflecting on 1:1s and trying to make them more effective for both of you. Just that exercise will pay off.