Making Proton Calenda as similar as possible to Google Calendar would be a great start. We are very used to using this platform, which is fluid, fast and intuitive, and the first full contact with Calendar is difficult.

The fluidity with which you can move events to the centers with your finger.

The range of colors for managing events.

Being able to move some events and calendars to others.

It would also be very nice to be able to synchronize Google Calendar and Proton Calendar via API so that in the transition between the two environments towards greater privacy, you can vary events in Google Calendar and have them synchronized in Proton Calendar.

In this way we would avoid having to initially be between two calendars that Proton gives you fewer options and then the change is a sacrifice that sometimes cannot be assumed.