A lot of updates have happened with SkQuery, the version currently is version 3.6.0, and there are new versions up to version 4.1.1.
Link to SkQuery and what new features it has:
https://www.spigotmc.org/resources/skquery-1-9-1-15.36631/
https://www.spigotmc.org/resources/skquery-1-9-1-15.36631/updates