That’s fair.

Haven’t read the spec but as an end-user I’d like simple toggles/options for each post. 

Nothing selected means post auto deletes in 90 days.

But if I go in and select to make it a permanent/eternal post I’d pay fee.

If I made a mistake and want to delete immediately I would (maybe) also pay. Not sure about this one though, seems like a good way to maintain the current way to make sure you don’t post junk just to do so.