REQUIRE source for changes to Family Tree
Just a simple suggestion: every change to vital information (birth, marriage, death) should require source documentation of that change. This would go beyond a simple statement to the effect that "everything matches." The change I suggest would require a source to be linked against the change so that it would be simple to go from the change to the source that justifies the change. It would also be simple to so from the source to all the changes that cite the source. If a source were deleted, the changes would be invalidated.