Headway was designed more for consumer use-cases than anything else. There's been some talk of adding the ability to customize it in the future but I don't have time for that because I need to focus on the basics first. You could fork it though, or just use some of the data automation (respecting the Apache 2.0 license). I replied to a child comment here but my recommendations for geocoding would be Pelias or Photon, and I like maplibre-gl-js. You can (should!) use planetiler for generating your mbtiles files and I've had generally good experiences with tileserver-gl-light, but many people recommend using PMTiles instead. It kind of just depends what your requirements are. For privacy-first stuff like Headway I can't require that people make requests out to S3 or Cloudflare, it has to be self-hostable which means a traditional tileserver is the only way to go.