Specifically, it's mostly the case that every raid type event that has a new exclusive kamihime to be gotten. Fun fact: no raid event has been reprinted yet; you miss one, you miss the girl.
The exception is... the Koihime Musou collaboration event; that is an advent type but still had two event kamihime to be gotten.

Once raid events are introduced, the event schedule basically alternates between advent and raid for a while, until union fight type events get introduced. After that point, the only real rule is that no event type gets repeated consecutively, with the exception of... again, the Koihime Musou collaboration event. That particular event is also odd in that it actually overlaps with a few events too (it spans like 4 weeks or so).

Advent type events from Ixion onward do have a kamihime liberation ticket for exchange, but it doesn't specify SR or above.