The ability to transfer things between tenants, and cloning of SharePoint sites.

The ShareGate PowerShell module offers many possibilities. And ease of use at the API level.

I like ShareGate's simplistic yet powerful interface that allows me to do things logically, like migrating from one site to another or from one library to another. The granularity it offers is awesome. I find the ease of use to be one of the best features. It makes management straightforward, allowing admins to make things happen within our environment. Additionally, compared to other tools, the initial setup was easy and straightforward. The simpler, the better.