Currently, when an accepted answer is deleted, the accepted "tick" disappears, but it would be useful to know that a deleted answer was the accepted one.
Proposal:
If an accepted answer is deleted, and no other answer has since been accepted, show a (greyed out) acceptance tick next to the deleted answer.
Note: I am not suggesting a change to who can see deleted posts, just a small change to the information seen when viewing a deleted accepted answer.