We added the following changes to Staging:

• Until now users could move huge sets of data with export/import mechanism in portal. However it was not possible to publish only a subset of data. We added this functionality for Web Contents, and improved the feedback given after a finished staging process. (https://liferay.atlassian.net/browse/LPS-165481)
• Staging can be used multiple ways, however following recommendations can make serious positive performance impacts on the staging process. This way the users will have more positive experience using Staging. We added some of the most important recommendations to the portal. (https://liferay.atlassian.net/browse/LPS-190129)