Allow changing event type
This could be done only within the same category like Advance-Map (triggers and BG events) or between any categories; it's just annoying placing a sign BG event and then having to delete it to make it a hidden item BG event instead (I'm just used to Advance-Map I guess).
I don't know if this really fits Porymap's model. There are no "categories"--they are all separate event types in Porymap.
I mean they're organized by categories in the game, and by page in the UI, so that to me feels like a category.
So you want to be able to convert a warp to a Sign, for example? Are these common use cases?
Well that might be useful, but I primarily mean within the same category (i.e. BG event to BG event).
How would you represent this in the UI? Wouldn't it be confusing that only certain events can be converted to other kinds of events? And would you expect the existing field values to be preserved when switching back to the original type it was?