Unity's 2019.3 is ready for beta testing. Among the new features available in this beta is a revamped UI and faster iteration with new "Enter Play Mode" options.
A link to a download can be found here, and all of the features and updates can be found on Unity's blog.
The last beta release of the 2019 cycle, Unity 2019.3b, is here and it comes packed with new features, improvements, and a completely refreshed interface. Download it to get an early look at these highlights as well as to explore the new Input System, post-processing in the Universal Render Pipeline (formerly LWRP), physics updates, faster in-Editor iteration times, and the debut of ray tracing in Unity.