Since the official release of React 19, I've organized my thoughts based on what I felt while applying it to company projects.
1. use() hook - You can now directly consume Promises or Context during rendering. When used with Suspense, the data fetching structure becomes noticeably simpler.
2. ref can be passed as a prop - You no longer need forwardRef. It reduces a bit of code.
3. Server Components stabilization - Since they can now be used outside Next.js, it's worth considering using pure server components without routing.
One thing to note: some libraries still don't support React 19, so check your dependencies before migrating.