Reading Nigel Calder's book "How to read a Nautical Chart" is an excellent book on paper and electronic charts. It is VERY relevant to today's experienced sailors, despite its rather unspectacular title.
Nigel describes many limitations of electronic charts and a glimpse of the future.
For example, in the high end commercial charting software it is apparently possible to query an individual sounding and learn the source of the data. This kind of info will filter down to recreational software.
The book made me feel both more aware of the limitations of electronic charts, as well as making me conclude that we were right in abandoning paper.