Unfortunately, this now means that I have to go back to the drawing board and figure out at what point it would make sense to add more decimal places in order to avert an inflationary spiral that will eventually result from lost coins ...
These are the fundamental errors in your logic:
(a) Lost coins are
deflationary not inflationary.
(b) There is no spiral. Just because one coin is lost there is no causative connection so that more and more are lost because of the earlier losses.