I saw much faster and more consistent build times moving from Gatsby 3 to Astro, though I also switched from React to Svelte. The new site also scores better on Lighthouse. Astro is not too difficult to pick up, so you could try building out a few pages of your site in Astro to run some benchmarks. With Vite vs. Webpack as the tooling and the option for partial hydration in Astro, on many sites you can expect a pickup in site and build speeds.