[meonkeys]

https://docs.nextcloud.com/server/stable/admin_manual/instal... is a great place to start.

So much depends on your use case. Can you say more about that? And what have you already tried? I'm skeptical their server-side tuning suggestions will improve your "initial loading delay" depending on what that means exactly. If you mean you see a slow cold cache page load of the Files app web UI (or any Nextcloud app, really) then I'd say that's common with many complex JS-heavy web apps, including Nextcloud.

FWIW, my Nextcloud web UI seems as fast as I'd expect. Roughly 5sec to load the Files app completely in Firefox (logged-in & warm cache) and this is roughly the same time Google Drive takes to do the same thing! Navigating folders actually feels faster in Nextcloud Files.

I'm not using the web UI except when I have to. I do as much as possible locally (e.g. editing docs, contacts/calendars/tasks). I mostly use Nextcloud for mobile and desktop file/calendar/contacts/photo/notes/tasks sync & share and it seems to do quite well at this. Server-side I did spend a lot of time tuning at first, but it has been stable for years once I got it to a good place.