I use org relatively normally, with notes, TODO items, and appointments
(active timestamps), and way too many of them scheduled to be done on
any given day.  I export all agenda files to a combined ics file and
then stick it someplace I can subscribe to it from non-emacs calendaring
software.

To do this, I first invoke the agenda (because I want to see that too),
and then, because C-c C-e is not bound in the agenda view, pick a random
item and hit return, and then "C-c C-e c c" to export.

I realize there is C-x C-w in the agenda, but that does something else
-- only exporting the items in the current agenda view.

So, I'd like to suggest having the export key bindings work in the
agenda buffer.   The problem is that many of them do not make sense
because there is not a single org file associated with the agenda.

My proposal is that C-c C-e should behave similarly to when in an org
file, but choices that require an associated org file should be omitted.
Specifically, I think the following options make sense:
  c c (ical combined)
  c a (ical all)
  P x (publish - choose project)
  P a (publish - all projects

One could omit P, because publishing and agendas are disconnected,  But
I don't see the harm in it working if someone types it; it's not like
they are likely to have meant something else.