One of the best parts of the Classic Doctor Who series stories was that the Doctor and his companions would get into trouble or the story would start with a misunderstanding between the Doctor and his companions and others because he was present in a place where he should not be or where he didn't have security clearance/authority/whatever to be. The story would be complicated by this fact and add an element of conflict and doubt because of his lack of credentials for whatever the circumstances were, and more often than not would actually start the story off with a conflict between the Doctor and whoever was in authority or control. Heck, in the days of the William Hartnell and Patrick Troughton Doctors, their arrival without credentials on bases and secret installations was usually a central element of the plot, and many a Jamie or other companion was detained for reasons that had more to do with unlawful and illegal entry than other stuff. During the Jon Pertwee period, this was largely gotten around by the Doctor's UNIT credentials, but once he was let loose in time and space again, the problem with authority was dealt with as part of the story and gave the viewers moments of fun and anxiety as they watched the Doctor and his companions have to extricate themselves from a sticky situation.
And then came the psychic paper. The New Doctor Who introduced psychic paper, a means for the Doctor to fit in wherever he found himself, and to get him access to whatever was going on without the need to extricate himself from these situations. While I understand the need for it in today's society where paranoia in officaldom reigns supreme and with the 45-minute episode format, as far as I'm concerned, the psychic paper took an element out of Doctor Who stories that I had really enjoyed.
What's interesting is that, with the end of "The Vampires of Venice", the Doctor doesn't seem to have his psychic paper any longer. I can't say that I'm displeased.