This idea bothers me greatly - on a number of levels.
1. We revere authors and their works "as is" - not as we wished they had been written.
2. Reading older works with unfamiliar vocabulary, terms, customs allows us to discover the richness of the past - and is quite easily done now with dictionaries on board ereaders, Wikipedia available on many ereaders, - not to mention reading on a tablet, with its search capabilities.
3. Tackling 'difficult' books expands & enlarges our reading skills, not to mention our vocabularies.
4. Older plot lines simply don't translate to modern times - e.g., the husband hunt, entailment woes, etc. Lost or mislaid letters as a plot device transmuted into misunderstood twitter feeds?
5. As noted several times above, Austen in particular has been already "modernized" by many authors. Why meddle with the originals? If you want modern technology, read one of the existing "additions" based on Austen's characters.
6. The only modern author that I am aware of that can 'channel' Austen's style & sensibility is P.D. James -- her Death Comes to Pemberley was a capable homage that fit seamlessly into Austen's oeuvre.