We will be adding the ability for administrators to expire external users’ access to entire site collections after a mandatory expiration period, as we discussed at Ignite 2018. That feature will be rolling out in CY19Q3.sanjeev commented
There might be time when you want to expired links that you shared rather than deleting the item itself after some period of time.
Last week we announced a new feature called Personal Vault that will be available soon for OneDrive consumer accounts. See this blog post for more details.
We have no plans to bring Personal Vault to our Commercial customers at this time, but continue to make investments in advanced security features that are unique to the Commercial service.sanjeev commented
Would be nice if you can password protect any folders or files that you want to share.