Hi Zoe!
While I can’t guarantee this feature will be available at any given time, I can say that the desire to customize recurring events with more advanced options is a huge request and we have some plans to get it more to users’ liking soon.
I would definitely post this in our feature request forum: https://theeventscalendar.com/support/forums/topic/events-calendar-pro-feature-requests/ because it’s a great idea!
Other than that, If you’re comfortable with some coding, I would check out our Themer’s Guide, you might find some useful guidelines there to help you out: https://theeventscalendar.com/themers-guide-to-the-events-calendar/
Sorry I can’t be of much help!