What I am really looking for is beyond our email, it's proper integration between calendar, contacts, and map.
I want to be able to share calendars with my family, and link contacts from certain events (birthdays, meetings, and also just meet-ups). I want those contact's addresses to be available as navigation destinations in the mapping app. I want to be able to bookmark ("star") map locations.
The first two are kinda achievable with Nextcloud and davx. Not rock solid but for me it works well enough, the part about the map seems more tricky on first glance