I don't use Outlook - would it be advisable to just delete it?
Absolutely.
Outlook provides mail, contacts, and calendar functions in a single app, and it's a first class Exchange client.
Apple's own Mail, Contacts, and Calendar apps, and though they are three different apps, they are tightly integrated. They can also connect to Exchange servers, but the in my experience, Contacts and Calendar have occasional compatibility problems with
Exchange servers. (I haven't seen any problems using the Mail app to connect to Exchange.)
How to decide if you should use Outlook:
- If you don't need server-based contacts and calendars, then Apple's apps and Outlook are equally good.
- If you do need server-based contacts and calendars, and your mail server is an Exchange server, use Outlook.
- If you prefer having a single app for all three functions, use Outlook.
At work we have an Exchange server, and my preferred client is Outlook 2016.
At home I don't connect to an Exchange server, so I use Apple's apps.
If you don't need Outlook, just delete it. Otherwise it's wasting disk space and — during updates — bandwidth and CPU clock cycles.