Recently made the switch to Graphene and am trying to get my main email away from outlook.com

What's everyone using for calendar event invites?

I have a mixture of some events that only I need to see, but others I send and receive invites to people using gmail, outlook etc.

Currently trying out free Proton, but it's a bit limited. For example if I make a recurring event there seems to be no way to edit or remove a single recurrence. Also would like to be able to use say simple calendar widgets with it. Edit, also discovered that invites sent from gmail to proton simply don't arrive.

Happy for a paid service provided I'm not treated as a product for advertisers to market to.