I have other solutions for many things and my Nextcloud is pared down to just my calendar, contacts, and some storage for the rare occasion I need it. It can be fit largely to what you need, frustratingly it does not have an ISO 8601 locale and tries to bully me into accepting regional norms like mm/dd/yy. It’s a cool piece of software and if I ever run another business, I’d give serious consideration to using nextcloud to organize ourselves.